I am Doctor Thomas, a double board certified US doctor in internal medicine and integrative medicine, with advanced training in several other fields. I am a clinician of over 20 years experience. I will give you an initial answer or ask you a question, but be sure to use reply to expert to communicate with me as needed
An allergic reaction would not go on this long, nor would it keep developing new blisters in a localized fashion like this.
If you have a picture, I can give you more detail.
In any case, from your description, I would assume folliculitis, which is infection.
The spreading with blisters can be typical of staph bacteria.
Do not try to wait for a dermatologist, which is not how it works in the US anyway.
Go to your OB, your GP, your internist, or to urgent care.
Today as possible.
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