WTH....

So yesterday I checked my CM and it was brownish pink, like the kind you get a day or two before your period arrives... well today after the 3rd time we BD'd (once in the morning, mid after noon, then just this evening) I have some pink light blood w pinchy cramps .. I am only on cycle day 17 & 6dpo... I can't be getting my period already... could I? It's too early for implantation bleeding I think?... my first pregnancy I didn't have implantation bleeding.. im freaking out...