question, questions, so confused

[babi]

hi. me again. been reading threads, instead of studying, anyhow. pls can someone explain implantation bleeding to me. i am so clueless abt this. i had sex on the 4th day of my cycle(7th of may) soon as AF stopped and plenty afterwards, but then went to the GUM for some other test and they recommended i take the morning after pill(10th) then i had some form of bleeding for 2 days, on the 15th till maybe 17th. didnt think i was pg till my boy started harrassing abt it a week ago, only started to panic like 2 days ago. so was that implantation bleding. I am so freaked now, cant seem to do aything else but sleep. Pls advice