Hard to get "hard" ?

Hey guys, always me , 22/m gay. I lately realized that sometimes for me it gets hard to get my D hard. I can't understand if it's for anxiety or just that i don't like the guy that much. But it actually happened with 3 people now , so it looks to be a serious problem. All of the 3 times we were both "versatile" and with 1 guy I went as active (top) , the other 2 as passive. Let's analyze the first case :with the first one , i had sex the first time when i was a little drunk, and had no erection problems, i did the top and was fine. but when i tried few weeks later with the same person (but not drunky) , it was little difficult to get hard. Now, it could be still both the hypothesis, since i dont really like this guy (not actually my cup of tea) but still, I know that alcohol helps relaxing and avoiding sexual anxieties, so alcohol could ve helped me that night. (So, is it about anxiety or i dont like him?). Now let's analyze the third guy. I'm really fond of this guy and was a bit anxious that night becouse it was really hard for me to get that date , i really like him, but i could not be able to get hard that night. So i went as passive and it was a terrible sensation for me and for him too i guess. This time i guess it's anxiety for sure, or maybe could i like him but still not being sexually attracted? Some months ago i ve had sex with a guy (he was 36 , a little older, but i like mature ones) and i was hard all the time. But in this case he was only active , so there was no hope for me to being top. I had no problems with him, he was cute and calm.Now that we have some informations. What's my problem? 1) Could i get anxious when i have to Top? 2) Could it just be that i'm not sexually attracted by some people? 3) Could it be that it's easy for me to get anxious in some stressful situations? How can i find it out? thank you guys, it's really important for me. I apologize for any grammar error.