It seems that you may be having urticaria
There may be some cause or it may be without cause..idiopathic.
Stress,weather,infection,worms,some diet,dust,fume anything can cause urticaria.
Blood tests may be done to find out some cause.
Antihistaminics like fexofenadine
may be taken till itch is relieved.
If embarassing , steroid in tappering dose would be helpful.
You consult dermatologist
for firm diagnosis and treatment.
I hope you got my answer.
Dr. Ilyas Patel MD