Af 7 days early or possible inplantation ? (After chemical)

I'm not sure if af is trying to show up early or not but it isn't due for another 7/8 days. I had a chemical the beginning of the December i was 6 days late when i got a faint line then tested again 2 days later and nothing. I started spotting for 3 days before 8 days of full blown cramping and bleeding. Af isnt due untill 8th of jan according to glow but i have very light pink when i wipe (sorry tmi) I've had very sore boobs for a couple of days now. I've tested with a opk as im not sure if my cycles messed up because of the chemical to make sure I'm not ovulating and even tho they arent positive there is a very visable line. (Tho i think i ovulated last week. With temps etc) Do you think it just could be af starting ? How long does it take to get back to a regular cycle after a chemical ? Any helps appreciated.