Unusual thirst a sign of pregnancy?

So I'm thinking I might be pregnant, and today I've been waaay more thirsty than usual! Yes I did have unprotected sex where he came inside me about 15 days ago. Can't take a test yet however, where as my period isn't due yet. But I have been having other symptoms such as minor cramping, back pain, white discharge, nausea, and sore breasts. What are my chances of pregnancy?