It’s ok to feel a little bit of remorse for it. Don’t use the both drunk thing to possibly make yourself feel guilty for “taking advantage” Noone is ever that drunk that they completely forget what they are doing, unless they blackout…so hopefully you didnt rape her in her sleep.
Booze is a lubricant…it makes the decision making process so much easier and non existant 
If this is your first time doing something like this then I can tell you not to feel too bad about it. If you have done this a bunch of times…then there is no reason for this thread.
And cheer up…you got laid.