ok.
so yes you had sex for the first time.with someone you didnt know. and it wasnt that great,
but it wasss hot and it made you feel good and it was sexy and when you think of it, it makes you horny.
it was your choice. you wanted to do it then and there. and he had a nice body and you liked it and you liked being able to make that choice. to have that power.
and like you said before. its not about it being your first time. its about the first time you have with a particular person... who knows when you might meet that person?
and your young and free and single right now. so you should enjoy it. and if that means having sex with someone who makes you feel good.. then so be it... dont make a habit of it, if you dont want to make a habit of it... its your choice. again.
you shouldnt be feeling bad, because it made you feel good. dont regret choices you make because it will eat you up inside... it was fun yes? yes. so then keep it as a good memory.. not a bad mistake.
one day youll have good sex with someone special.. and then that sex will mean something special. this sex was, lets say... practise. yes. and good practise it was...;)