Confused and Scared

Anesha
I'm going to try to make this as short as possible. April 2015 I gave birth to my son. His father and I didn't wait the full 6 weeks after having him before having sex. I started having pregnancy symptoms again but when I took a home pregnancy test it came back negative. At my 6 weeks check up they gave me a urine test (before giving me my birth control shot) but the nurse watched the test for far too long before determining if it was positive or negative. She gave me my shot and I left. As time went on my symptoms got worse. I took 5 home pregnancy tests, all 5 had 2 lines and the longer it sat one of the lines disapperared so I assumed it was negative. July 2015 I had a miscarriage. Now I'm having pregnancy symptoms again but my tests are coming back negative again. I usually have my period for 5 days but the last few months it's only stayed on for 3 days. If my home pregnancy tests are coming out negative then I'm sure a urine test I take at the doctors office would come out the same way. I know none of you are doctors I just really need some feedback about what to do.