If you are taking progesterone/ progesterone in Oil.......then yes its normal.
Plus, you're still recovering from egg retrieval, so your ovaries are swollen and may also contribute to the cramping.
I had my embies transferred on Saturday and have been having the exact same symptoms as you are.My back has been on and off sore, and cramps here and there, not so much today though. My Dr after the transfer did tell me to take it easy though and not to be jumping around or going for a run because my ovariaes are still swollen and could cause cramping too. So I have been relaxing all week. Try to take it easy. The progestone can cause some of these symptoms too!