bumps and itchy scalp

Dear Sir

Greetings

i am a 23 year old male. from past few years i am having red itchy pustules or some time red bumps on my scalp,skin on scalp becomes tender. It happens always now and then. I had have some oral antibiotics like amoxycyline and potassium and shampoo like Ketoconazole. Initially it helped me when my scalp became all clear in a week only but it appeared again. i have stopped taking english meds as they were too heavy on my digestion system though i still apply the shampoo on alternate day. i have also problem of acidity, gas and my bowels don't clear everyday. with this i have problem of hot and cold too,i am always having cold issue around the year when weather changes or i eat rice,curd and drink any cold item. please help me with your valuable suggestion that what should i eat and med i should intake. Thanks