Am I a massive snake??

Ok so I've got myself in a little bit of a pickle. About a week ago I slept with a guy in my vague friendship group who I don't really know too well (but we got on well enough). The problem is this guy dated another girl in our friendship group for a while during first term (maybe 2 months?). I'm not massively close to this girl, but I'd say we were friends. They broke up quite a few months ago because he cheated on her multiple times (making out with other girls). They seemed to be getting along fairly civilly although she is still upset. Having sex with him was a mistake was a dick move, I know. I was very drunk and not really thinking of her at all. However, I get the feeling she knows about it as she has been very cold to me over the past few days but I am not sure. Should I tell her?
Another dilemma lies in the fact that I told two mutual friends who are close both to me and this girl that I made out with this guy and they didn't seem too fussed, but I neglected to tell them we went all the way. So I essentially lied to them, which is making me feel a little terrible. Should I tell them too? Or should I just hope this issue vanishes somehow? Thanks.

Depends:

Do you have a long & slender body?
Do you slither everywhere?
Do you make a 'hissssss'ing sound?
Do you have sharp teeth?

If you answered yes to any, you're probably a snake :/

Ok so I've got myself in a little bit of a pickle. About a week ago I slept with a guy in my vague friendship group who I don't really know too well (but we got on well enough). The problem is this guy dated another girl in our friendship group for a while during first term (maybe 2 months?). I'm not massively close to this girl, but I'd say we were friends. They broke up quite a few months ago because he cheated on her multiple times (making out with other girls). They seemed to be getting along fairly civilly although she is still upset. Having sex with him was a mistake was a dick move, I know. I was very drunk and not really thinking of her at all. However, I get the feeling she knows about it as she has been very cold to me over the past few days but I am not sure. Should I tell her?
Another dilemma lies in the fact that I told two mutual friends who are close both to me and this girl that I made out with this guy and they didn't seem too fussed, but I neglected to tell them we went all the way. So I essentially lied to them, which is making me feel a little terrible. Should I tell them too? Or should I just hope this issue vanishes somehow? Thanks.

Ok so I've got myself in a little bit of a pickle. About a week ago I slept with a guy in my vague friendship group who I don't really know too well (but we got on well enough). The problem is this guy dated another girl in our friendship group for a while during first term (maybe 2 months?). I'm not massively close to this girl, but I'd say we were friends. They broke up quite a few months ago because he cheated on her multiple times (making out with other girls). They seemed to be getting along fairly civilly although she is still upset. Having sex with him was a mistake was a dick move, I know. I was very drunk and not really thinking of her at all. However, I get the feeling she knows about it as she has been very cold to me over the past few days but I am not sure. Should I tell her?
Another dilemma lies in the fact that I told two mutual friends who are close both to me and this girl that I made out with this guy and they didn't seem too fussed, but I neglected to tell them we went all the way. So I essentially lied to them, which is making me feel a little terrible. Should I tell them too? Or should I just hope this issue vanishes somehow? Thanks.

Ok so I've got myself in a little bit of a pickle. About a week ago I slept with a guy in my vague friendship group who I don't really know too well (but we got on well enough). The problem is this guy dated another girl in our friendship group for a while during first term (maybe 2 months?). I'm not massively close to this girl, but I'd say we were friends. They broke up quite a few months ago because he cheated on her multiple times (making out with other girls). They seemed to be getting along fairly civilly although she is still upset. Having sex with him was a mistake was a dick move, I know. I was very drunk and not really thinking of her at all. However, I get the feeling she knows about it as she has been very cold to me over the past few days but I am not sure. Should I tell her?
Another dilemma lies in the fact that I told two mutual friends who are close both to me and this girl that I made out with this guy and they didn't seem too fussed, but I neglected to tell them we went all the way. So I essentially lied to them, which is making me feel a little terrible. Should I tell them too? Or should I just hope this issue vanishes somehow? Thanks.