Re:"Blood Clots" in birthmark
Wow, this is very troubling! I've never heard of this as a symptom of PWS. Certainly I've never experienced it.
(37 facial PWS several treatments here.)
Are you living in the US? This almost sounds like some sort of Nematoda living under the skin. You should find a good doctor quickly! This could be a big problem!
-And please keep us posted!