I got AF at about 3 weeks PG, (I didn't know I was PG at the time). I found out with a +HPT at 7 weeks, which was then confirmed by a BT. I still don't really feel PG, no m/s, not that tired. I was still getting to know body after coming off BC, thought the sore BB and cramps were signs of AF and/or Ov. If it wasn't for the sore BB, I would feel completly normal (which I only really got at about 6 weeks).
I hope everything goes your way, good luck.