thanks for writing to health care magic.
Your baby should be investigate for various other problems which cause bruising.
various problems can be associated with such bruising.
Other than disorders that can cause such bruising you should also consider child abuse that may cause such problems. Keep a watch on maid, care taker etc.
the platelet count
cannot be 252. Since your doctor saw your report and mentioned it as normal, I presume that there was some error in the report typing