Cold, sore throat, headache, allergies.

Hi I am getting cold very quickly even small change in weather. Currently I am in Bangalore from last 12 years.This cold will be 1 week and getting 2-3 times in frequency of 3 months. Due to this cold some times I am getting throat infection and head ache some times. Head ache is more if I take headbath and hot sensation in eyes. Some times due to this cold I am getting small red skin bumps with itching. From last 3 days I am feeling something stuck in Throat and little cold also. Please advise is this any allergic issue like sinus or any acidic problem Do I need to go for any allergic tests? Home remedies (salt goggles and spices drink, green tea) am following as of now with taking of citrizen tablet. Some times feels better and will reduce also. But looking for permanent solution . Thank you in advance and guide me to which doctor need to consult. I mean ent or gastric or allergic expert.