Am I pregnant or no? I am unsure

2 wks ago I started having frequent urination I went to urgent care first they said I had a UTI then two days later told me to stop the meds cuz I did not have a bacterial infection. Sun the 16th I started this, abnormal to me, period it started off bright red and light and I normally start off dark and heavy, then come Mon it was medium then Tues it was light it went away then came back light then Wed it was brown discharge then it stopped completely. Thurs & Fri I started to cramp and spot. I called my dr office told me to take a preg test. Sat I took a dolla preg test came back neg then I looked at it a hour or so later and there was a faint pos line. I googled and heard if you wait too long there could be an evap line but I had taken the same test in the past and never showed a second line at all even a day later. Mon called dr office back with results told me to take another one asap took around 12pm it came back neg then I went to the hospital bcuz if I'm not preg why am I vomiting, have nausea, cramping, headaches, peeing like every hour and very tired can't get up in the morning. The hospital did a urine test it was neg and did other blood work told me I'm perfectly healthy, well the test I took b4 ER was a faint pos when I came home. ER told me could of miscarried. I'm still annoyed bcuz idk what is wrong with me. Took another hpt yest came back faint after 2hrs. Dr office said I could be early and that's why pos taking so long to show. Dr appt 4/14/14. I am 27yrs old and never been pregnant