Could it be implantation bleeding?

So I was supposed to start on Nov 4 and didn't. My fiance and I had sex about 4 times through my fertile window. I didn't have the usual cramps or anything that signalled it coming. Yesterday there was a brown spot on one of the pads I've been wearing just in case. Today I had a few sharp craps but r nothing happened and nothing was there when I wiped. A few hours later I had to go to the bathroom again. I haven't been cramping or anything at all since that one time which is really unusual because even if I'm late, I always start cramping a couple days before. Well there was some white-ish pink cream looking stuff when I wiped this time. Could it be implantation bleeding or am I just reading into it and my period is acting up?