That was the NUMBER 1 sign for me when I was preg with my DS, I was a big drinker back then and I could throw down the drinks like no other. Before I found out I was pregnant I could barely drink 2 beers and I wanted to barf. It all made sense after I found out.
And last month I had some drinks for our anniversary and after a couple drinks I wasn't feeling it. That's when the suspicion began....which was right!
I hope its a good sign for you