TL;DR I finally am having success with women, but I'm left wondering "why the heck do you like me?". I feel like a sham when girls like me more than I like me.

Background

Was a nerd, not successful with girls growing up. Had first girlfriend for half a year, about two years ago (now mid 20s, Midwestern US). Was still mostly been a dweeb, just a more attractive one.

Current

Have life in order, have genuine self confidence now and not the anxiety any more. Powerlifting totals are something I'm feeling better about, and have self worth and am comfortable in my own skin. Used to think I was unattractive physically, despite some girls actually liking me for my looks before getting turned off by dweeb personality, but now am satisfied with appearance.

Current situation

Been lurking TRP for about a year now. Everything is better in my life, except success with women. I self-effacingly joke to close friends "nah I'm not dating anyone cause you know I'm a loser". Then again I honestly don't think I'm a loser in much of anything, except with the opposite sex.

The quandary

Thus, the times when I am having success with girls, it feels bizzare. A hot girl will be laughing at my dumb joke, going out of her way to hold the door for me, or giving me her number . . . and meanwhile I'm thinking "that wasn't actually funny at all" or "she's just giggling to seem nice" or "she won't text me back tho".

The same thing happened back when I was in a relationship. I would silently wonder "why do you love me". I tried and thought I was a decent boyfriend, but it was not nearly commensurate with the doting and obsessiveness she showed. I thought I was reasonably attractive, but she thought I was waaaay more attractive than I thought I was.

So what the heck am I missing here?

Not everything needs to have a "why" answer. I don't run around like a young Tom Edison asking for a "why" to every single thing. Yet when I follow Seddit and TRP advice and have success, I'm left wondering how I just hoodwinked some girl. Makes me think I'm just appearing to have success, not actually having any; like the Bernie Madoff of seduction as it were.

Of course I can read Matt Ridley and TRP theorists on "why" men and women and humans act certain ways. It makes sense in those contexts. It still doesn't explain why I make a shitty joke and the girl likes it, nor why my hair's a mess and eyes have black bags yet the girl is clearly physically attracted.

Diagnosis

Is this a case of inner game not up to snuff? Is this normal for a recovering AFC? Is this too much brain power focused on any neuroticism within? And how do I change this? How do I go from thinking I'm just tricking girls when I'm following the RP playbook without knowing why it works?

All the RP advice in the world can help my life and help my XX success. But what do you recommend to make me believe that I deserve it or have earned it?

Any advice or recommended reading is appreciated. Thanks in advance.