Implantation bleeding!! Help..

Angel
I had my last period starting on April 20th and last Saturday and Sunday, May 7th and 8th, I experienced cramps, much stronger than When Im Having my period. I hardly have periods cramps and when I do is very light. So, monday morning I notice a very very little CM light pink in the morning, nothing all day. Tuesday the same, and yesterday, wenesday the 11th a bigger blood spot only in the morning, darker pink, only stained my panties, and disappeared. Nothing else untill now. Im not expecting my AF untill the 18th at least. Could that be implantation bleeding? Any of you girls had this experience before? Thank You!