Possible implantation bleeding?

My fiance and I had unprotected sex about a week and a half ago... not thinking I could get pregnant bc i was on depo until last nov. and quit for personal reasons (weight gain, headaches, ect) well i didn't feel like i needed other birth control until i got bk to a normal cycle which i still have not. I have not had a period but i have had one time of bleeding that was light and spotting here and there when i first came off of depo, since I quit my depo shot but don't know if i would classify it as a period bc i don't know if i ovulated or if it was just bleeding from coming off depo bc now i haven't had any of it since. But now today I have had slight bleeding only when i use the restroom it ranges from light pink and brown to a slight red. I went to my GYN on monday for my annual check up and he notified me that you do not have to bleed in order to ovulate which is something I never knew... so now with this bleeding I am wondering if it is possible implantation bleeding and how long I should wait to take a test we have children but I always had a period to miss that I went off of to take test so this I am unsure of with timing due to no periods. Has anyone else had this issue or went through this and what were the outcomes? Could it be implantation bleeding?