This can happen but it is rare. You should go inf or a follow up to have your doctor look at it and make sure.
If your hair does not grow past 3mm then it may be the old transplanted hair that never shed (or came out). Follow up with your doctor.
Some of the transplanted hairs might remain in their grafted position. At 10 months, they should wash out, but it you take a forceps and pull on it, it will come out with no pressure/ These little hairs never grow as they are remnants of the old hairs.