I have a complicated situation but I’m scared I might be pregnant!!

Okay so I take birth control, but I always move to the next pack early so I don’t get my period (my doctor said that’s safe) I use a condom and pull out when I have sex, I decided to stop taking my birth control for 4 days to see if I would get my period, I had really bad cramps but only bleed for a couple of days, could this be implantation bleeding meaning I’m pregnant? Or do you think it’s just a light period because I haven’t had it in a while and I stopped taking them at a random time? I’m sorry I always over think things like this I just need reassurance, I would take a pregnancy test but I don’t know when is the right time since my cycle is so messed up because of my pill