Had withdrawal bleeding

I had sex on bc without a condom all weekend last weekend. Then I couldn’t take my bc due to insurance problems until Wednesday. So from Monday to Wednesday morning I didn’t take it. Tuesday night until Wednesday morning the bleeding was heavy but not like crime scene. Then through the day yesterday it was barely even spotting. Just woke up to very pink spotting. Is that implantation?

Also bare with me I’m totally unsure of which group this belongs in!