spotting, dizzy, cramping, test 2positive, 2 invalid, 1neg

had gottin my period 2 days late. I had a little bit of pink spotting. I thought I was getting my period. I checked again later that day & there was nothing. The next day I went pee & I was bleeding a lil bit. I put a pad on & later was nothing. 2 more days went by & I had brown spotting. Normaly my periods are really heavy & I have them for a couple weeks straight. This does not seem normal for me. I took 5 pregnancy test... 2positive, 2 invalid, 1negative. Any Advice or help?