please help

I have 3 faint positive test. 1 first response and 2 are cheap ones from Wal-Mart and family dollar.

this is my first time really trying to get pregnant. I have to little ones already. Ok last week I tested 6 days before my period it was VERY VERY POSITIVE! then I kept testing that day bc I was So shocked. I went to the Dr two days ago they did a urine and blood test both negative. the blood test was <1 (idk what that means) I tested last night and another faint positive. tested again this morning and its a little darker. I'll try and post pics. oh and my period is due tomorrow.

symptoms:

sore boobs on and off

headaches

Diarrhea on and off (sorry tmi)

metal taste

Cervix has been high closed and firm for 2 weeks now I checked the CM today and it was Cle

ary and sticky