Drinking and maybe pregnant?

Before I go into it, I know a doctor is the best person to talk to and I'm booked in for end of week for a check up because I am worried
but just wondering if somethingvsimilar has happened to anyone...

I was out drinking but I felt fine. Just tipsy. and was sitting down and almost fainted.
Everything went blurry, slow montion, I couldn't hear myself speak, everything was white noise and then I just threw up.
I'm not on medication, and usually hold my alcohol quite well.
This has never happened before it was a very strange feeling!
I'm hoping I am not pregnant but could this be the case? Has anyone had any strange experiences where they have been pregnant and drank alcohol...?