implantation bleeding?

This is the first time ive ever posted in a group like this before. So im very confused and im thinking im pregnant but not sure. I had my period on july31 ended august4 then on the 15 i noticed i had like a yellowish pink discharcge that only lasted about an hour or two. Then the next day i had some more and also a light brown discharge and light bleeding for the next day. So since then ive been bleeding enough to where i had to wear a pad. Today its been almost a week n im still bleeding but its lightening up. Everything ive been googling says in pregnant and its implantation bleeding but is it still inplantation bleeding if ive been bleedi g this long n this heavy? I mean its not heavy to where theres blood clots but its heavier n more red than implantatiin bleeding is described. Im so confused i just want to know already. I took 4 pregnancy tests all came out negative. Ps i had unprotected sex everyday from the last days of my period till the second 'period' came