Could i be pregnant or is it just wishful thinking?

I haven't had a period since I got off dept 3 months ago and I've taken a few pregnancy test between then and now all of them resulting negative. A week ago I noticed my nipples were getting really sensitive and seem fuller. I don't have any other changes or "symptoms" to indicate I would be pregnant. I'm hesitant to take another test and have it be negative. Could I be pregnant or is it just wishful thinking?