Thanks for the query.
This presentation can be seen with many skin diseases. The best option is to consult a Dermatologist in person to understand the problem and get it diagnosed. A proper treatment can then be started. Discuss the situation and hope it will be cleared in few days. Don't delay the appointment. You can use a bland moisturiser till then and OTC anti-allergic medications.
Based on your description, it appears that you have intermittent variable of chronic urticaria.
These conditions have a strong relation to one's internal health and it needs to be evaluated as often quoted - Skin is the mirror of internal health