You are suffering from Acute urticaria.
Urticaria can occur because of various reasons like Viral or bacterial infection, medications, pollen, dust, certain food items, heat or cold exposure etc.
Take Wysolone 5mg thrice daily after meal for 5 days
Bilashine 20 mg SOS for itching
Cap pan d in empty stomach for 5 days.
Avoid the triggering factors which leads to skin rashes and you need to identify the sources for example whether it's because of food or medication or dust or any other thing.
Because only by avoiding the triggering factors you can manage this condition.
Hair fall can be because of
Vitamin D deficiency, Iron deficiency, Dandruff or it can be Androgenetic Alopecia.
Check for Vitamin D levels
Do Iron Profile and DHT test.
If vitamin d is Deficient then take Uprise D3 60k cap once a week for 8 weeks.
For decreased iron levels you can take Haem up syrup: 10 ml once daily after meal for 3 months.
For Dandruff you can apply KZ Shampoo: Twice a week for 2 weeks
And lastly if DHT levels are high then apply Mintop 2% solution at bed time for atleast 6 months. But i would recommend to consult a Dermatologist in that case.