I know this is a bit long but I would really appreciate all thoughts, insight and advice.

So, I've been dating this super nice girl for a few months now. We're both 18. She's very submissive to me and does everything I want her to do, basically sees me as a god, her master. She cancels other plans to see me, compliments me a lot, initiates 90% of the physical touch, always dresses nice for me, does her hair, hygiene etc. She's been pushing for exclusivity for about 2 months now and is completely in love with me.

She's a virgin and started exploring her sexuality with me thanks to the advice I got here before. So far she gave me a few blowjobs, always came on her face. I've fingered her, ate her out etc. We tried having sex before, but I couldn't keep it up for some reason, maybe because it was after she gave me a blowjob and I came from that already. This happened about a week ago, so I looked up some older posts here about erectile dysfunction and decided to lay off masturbation for a while, as suggested. Not sure if this was a good idea. I tried keeping busy but my other plates sent me nudes and shit so I got hard and edged myself without cumming.

I came over to her place yesterday, we were chilling, then started escalating. The vibe was really good, we both got super horny. She started blowing me and I could already feel I was unusually sensitive, so I would stop her occassionaly and finger her, talk to her or something. I went down on her and she was really enjoying it, pulling on my hair etc. At this point I'm horny as fuck. I put on a condom, this time I had no problem keeping it up, but as soon as I put it inside of her I came. We laughed it off, I told her I was probably too excited and that's what I honestly thought. After an hour or two we went for a second round, we both got really horny again, I fingered her and ate her out, then she went on her knees and as soon as she started sucking on my dick I just came again. At this point I'm just disappointed in myself and visibly upset, which I never am in front of her. She comforted me, said it's okay and that she doesn't mind at all.

I watched her behavior after that, to see if anything changed and if she started seeing me as weak. Everything seemed to be as usual. Compliments, touching, cuddling, telling me how much she loves me, asking me to grab her by her neck etc. We took a shower together and I showed her a good time in there as well. We went to sleep and in the morning all was as usual, we had some more action, she made us breakfast and I went home.

Just to clarify, I'm not a virgin, I've had ONS', FWB/plates, etc. I'm not a sex god either, though.

1. Is anything wrong with me or does this happen to some of you experienced guys as well, occasionally?

2. What to do from now on so that this never happens again?

3. Should I expect a change in her behavior? Does she possibly see this as weakness, or not, considering she isn't just a plate?

All advice is very much welcome!