What if u took a pregnancy test and it said not pregnant but still suspect a pregnancy?

This is the same problem I am in. I was at Walmart 2 days ago. I've been worried about being pregnant for 2 weeks.. I had no money on me but a few dollars. I bought a 88 cent pregnancy test. It showed up negative but I've been having ALL the symptoms. Plus I'm 2 days late on my period. So if I don't start soon.. Over the counter pregnancy tests can't be trusted. So id suggest going to the doctor. That's what I'll end up doing. I just don't know how to break the news to my mom..