Discharge

I have a little darkish brown discharge. It’s not very thick, looks more like old blood coming out . I had sex about 2 weeks ago with a condom and we used pull out. I’m also on the pill for about 8 months . I’m supposed to get my period in 3 days. I’m having light cramping. I know you can experience some spotting and cramps on the pill before your period but I usually don’t, that’s why I’m a bit nervous it’s implantation bleeding. Is there a chance that it is?