hi the itchy red welts u r complaining of might be scabies
infection as u r giving a history of overnight stay/sleep. nothing to worry if it is so ,what did the doctor examined u said an infection? did it comedown after antibiotics u did not mention? the first treatment for scabies is exposure to sunlight daily for atleast 2hrs, start permite ointment /cream daily twice leave over and expose to sunlight ,tab allrite-d twice daily for 3days for itching,tab nexprofast40beforebreakfast,tab acceclo-ptwice daily afterfood, use dermadew permithrinsoap/tetmosolsoap regularly,make sure ur clothes and linen evrything washed properly in hot water and exposed to sunlight.make sure ur closedones do not use ur clothes or linen as scabies mites can be transferrable .