This began life as a reply to someone on /r/questioning, but decided to archive it for myself.
(paraphrasing to anonymize)
OP has just started their first romantic relationship with someone they have quite a bit in common with. OP enjoys spending time with their partner, but didn't feel anything special during their first kiss. OP would be fine with kissing them again if requested, but it's not something they felt that they would specifically desire or seek out.
OP recognizes that they generally don't quite understand romance or attraction, so being in a relationship is somewhat difficult already, but in an effort to understand their partner better, they wanted other perspectives.
OP's main question: "Do 'regular' people actually desire physical affection? Like, do they look at their partner and feel a physical urge to touch/kiss them, or does it originate in some concious 'I want to touch/kiss them' thought that then begets an action?"
Do people actually desire physical affection?
For me, 'yes' isn't strong enough.
I don't just desire physical affection, I need it. In fact, I sometimes don't feel as if my feelings are properly expressed without employing physical affection. Past that, I can get irritable, depressed, and lonely during prolonged periods without it. It affects my mood on a deep level, and it's something I need in order to function properly. I don't think I could stay in a monogamous relationship that lacked physical affection.
BUT, if that's something you don't desire or need, then that isn't weird, it's just a part of your particular flavor of awesome. "Normal" or "regular" people aren't a thing, and I discourage anyone from trying to compare themselves to a baseline human configuration of wants and needs. Evolution-based life doesn't operate like that. Evolution is dependent on randomness, uniqueness, and mutations, then it keeps the useful ones around over time.
To this end, I encourage you to ask yourself: Where your idea of "normal" comes from? From your parents? Peers? Media? A combination?
Also, what is to be gained by people who reinforce this notion of "normal"? Do they earn money from it? Do they feel accepted or powerful by being (or claiming to be) a part of the "normal" group? Do they use it to otherize those who don't fit in the "normalcy" they so enjoy?
There's deep introspection down that path, so here's a lighter take: I don't have to understand you to respect you, but more importantly, I don't have to understand you for you to deserve my respect. You don't deserve respect because you fit in my definition of "respectable person", you deserve my respect because you are a human.
For example: I don't understand what it is to live in an existence where physical affection does nothing for me, but that's ok. My inability to empathize fully with your situation is not a failing on my part, and especially not on yours. I have to accept that yours is a perspective that I will never fully grasp, but also that **you are still valid**. If someone is unable to respect you, that's a them thing, not a you thing.
Above all, don't feel like you have to push yourself to do things that you're not comfortable with. In our current society, there is definitely a tendency to push for obtaining romantic relationships and putting them on an ever-escalating path towards monogamous marriage (most commonly referred to as the Relationship Escalator).
There's a societal expectation that you date to marry forever and that's the best path for everyone, but it doesn't have to be that way. You are a unique person, your partner is a unique person, but also, the relationship between you and your partner is a unique entity of its own. Just as you don't have any responsibility to look or act or be a certain way, your relationships with others don't have to look a certain way.
All that to say: If physical affection is something that you don't want or need to be included in your relationship with another person, then by all means, you shouldn't feel obligated to shoehorn it in. Human relationships are best when they're mutually beneficial, and beneficial relationships tend to be stifled when one forces themselves to be someone they're not for the sake of the relationship.
That is my perspective, but don't take my word for everything. Try things out, figure out what works best for you. I greatly appreciate that you specifically expressed your desire for other perspectives. That is a valuable and [seemingly] rare trait, and you should be proud of that. Keep following that curiosity and openness.
If you would like more perspective, I would take a look at /r/asexuality, /r/demisexuality, and any other subs that may interest you from their sidebars and wikis. Follow your nose, ask questions, and read about the experience of others.
Also, while I am not directly recommending polyamory for your situation, a lot of understanding can be gained from that community about the nature of relationships. It was certainly a catalyst for shifting my own perspectives when it came to relationships. /r/polyamory, and the resources documented there is a good place to start. Decide whether it's for you or not, but I would recommend checking it out, if only in the interest of gaining new outside perspectives.