implant removed...help! sorry for long post!

Maddie • Trying for baby #2! 👨‍👩‍👧
I had my implant removed 13 days ago and I haven't had a period yet. We had unprotected sex few days after getting it removed and we had sex night before I got it taken out. 
Few days after the unprotected sex, I woke up really sick and have had migraines all week (I had that with my last pregnancy) and now I've been having cramps (which I had with my last pregnancy) and last time, when I went to the docs after a few weeks of cramps he told me I was 5 weeks pregnant and it was my uterus expanding. 
I have no idea what to think this time!! No other symptom a but cramping, tiredness, sickness and headaches. Test was a negative. Could I get pregnant this fast? I had the implant in for 9 months.