everything seems like a symptom :-(

So why when you are TTC does everything make you think you are pregnant?!  
AF was due yesterday. I wasn't feeling great on Monday so I took a test- negative. Still no AF but I feel crampy. I also have a bad cold. So that totally could be the reason for my late AF.  Do my boobs hurt or am I just imagining symptoms?  UGH. When should I take another test?  The one I took on Monday was a clear blue which I found out is less sensitive than the early response one I usually take. I just don't want to see yet another negative!!!