Brief Answer:
Cab be boils or urticaria.

Detailed Answer:
Hi.
Thanks for your query, albeit small and specific.

You have just noticed today after having a shower.
The most probable causes of such a problem can be:
-Multiple boils.
-Allergic dermatitis to something on which you had sat.

Would you please some further information so that I can help you more.
Are you diabetic ?
Is there any pain or itching or without any symptoms ?

I would suggest you the following:
Wait and watch and if possible let this be seen by a Doctor as the direct visualization by a Doctor can get us a more proper diagnosis.

Till then you can apply liquid Povidone Iodine to the whole area and let is dry on its own. This will act to make the skin sterile and not have secondary infection.

The presence of pain, itching, redness indicate that they can be just boils and may get alright on its own; a supplementary course of an antibiotic and anti-inflammatory medicines can help early and complete resolution.

In some cases, as seen in practice, this can be a local dermatitis type of reaction giving local urticaria, elevated skin nodule. These may settle on their own or rarely require antihistamine and steroids small course.

So it is better be examined by a Doctor if possible.

I hope this answer helps you to get a proper diagnosis, and get a proper further treatment. Please feel free to ask for more or if you need further clarifications if you feel there is a gap of communication.

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