Could increased thirst mean pregnancy?

So recently my boyfriend and I had sex and I was on the second day of my ovulation cycle (which is now over with). Since then I've noticed my lower belly looking a little more rounder than usual and I have had an increased thirst. We've had sexual intercourse before, and I've never came across these side effects besides the bloating which usually lasts a day. Could an increased thirst for water be a sign of pregnancy, or am I over thinking this? This has been going on for about a week now and I'm getting slightly worried.