I am not sure exactly what this irritation might be, although hives
is one possibility. Hives are an allergic reaction in the skin in which blotches of raised, red, and itching skin appear, typically coming and going or fluctuating in size. They are typically caused by exposure to something you are allergic to, but they can also be provoked by a number of other causes, including common viral infections.
Another possibility is that this is contact dermatitis, which is a painful condition in which the skin breaks out in reaction to a substance that it has come into contact with, usually a new or different soap or other chemical.
I suggest that you go to see your primary care doctor
right away about this, as they should be able to help figure out exactly what this is and also give you some medicines to help reduce the symptoms. If you have any other symptoms of a more severe allergic reaction, such as swelling of the face or trouble breathing, then you should not wait to see your primary care doctor but should, instead, go right away to the emergency room for a quicker evaluation.
I hope that you are feeling better soon!