So me (20M) and my girlfriend (22F) have been having sex for about the last couple of months here and there and especially as of late, however something happened today and while I'm probably being paranoid, there's a few other things on my mind. So today, to be fair, we smoked weed, and then we did our usual, I enjoy eating her out and she enjoys it too, she came more than once today, however, I only managed to get hard once today, and after that it didn't come back no matter what I did, be it masturbating myself or getting head or really anything, it startled me a bit, and while I'm willing to blame it on the weed, the issue is that every other time we've had sex, I do only get hard a couple times and it really comes and goes.
So that's the situation, now about me, this is really my first time having penetrative sex, but I've had oral and other things before, however all those other times I've never really cum and also had some issues getting and even really staying hard. I'll be real, I was kinda masturbating every other day for the last year or so after my last relationship and before this one, I'd sometimes take breaks, I'd sometimes go basically daily, but now in the relationship, it happens maybe once a week or so, however it's really weighing on my mind that maybe all the masturbation has somehow fucked me up (the masturbation is almost exclusively with porn which also worries me), so I'm curious about 2 things, A) Could the masturbation habit be an issue, if so, what to do there? B) In general, what is considered normal and common in terms of getting and staying hard, I'm not really well versed in the topic and I would like to get the answer from a somewhat more "personal" level rather than just reading a paper/article haha
I guess some more information to add though I don't know how to structure the rest of the message around it, so I'll just throw it here at the end:
I don't think the issue is with not feeling the intimacy or the care, as far as we've talked we really both enjoy it and it's just that we'd both like for me to cum and all that, it's an experience I wanna have and I want her to have and having this struggle both makes me a little upset because I wanna comply, but also other general patriarchy bullshit you get thrown in your head often, with the whole "men have to be bulls with infinite stamina and permanently erect penis" or w/e. Another thing would be that this is the only time I just can't get hard (and this is also the only time we've used substances while having sex), before it's happened (as in, getting an erection) and it goes well, but it is never really easy to get me there and when it goes away, it takes a while to come back. Also, regarding the masturbation, I guess I never thought about it before given I wasn't having sex (or realistically even thinking about it orz) but I have steadily noticed more of a problem to even get an erection and even ejaculate, I can do it on my own time but it takes a while and I guess I haven't given much thought to my own enjoyment in sex in general, so maybe that's a thing? Although I wouldn't really know where to start. I guess a separate issue I've noticed is that in general I'm not really stimulated by my own dick anymore? Or rather, it's progressively harder for it to feel extremely pleasurable, it feels fine and even comfortable, but no real shocks in my body or similar things.
Thank you for reading, I'll answer any further questions you might have before replying, thanks in advance!!