M.B.
C.,
Glad you called OB and got an appointment - while waiting - CALL the dermo and tell them it's unbearable! Ask them what to do? If they continue to make you wait for the appointment (no idea how far it is out) get a new dermo.
It *does* sound like something pregnant women get, but I haven't had. A milk bath may help (Body shop or other store similar has this, or find a recipe online).
Sounds silly, but don't scratch.
Are you drinking enough water?
Baby calls, hope this helps,
M.