Suffering from continuous cold and sneezing

I am suffering from frequent cold and sneezing problem for almost a year. Actually in my childhood i suffered from pneumonia also but after that everything was okay. But regular cold and nasal congestion kept going and at the age of 15 i saw an ENT specialist also but at that time they said nothing special. After that i don't remember exactly about my problem. Maybe everything went well during those days. Now 1.5 years back i suffered from a severe cold problem due to my hectic job schedule i couldn't protect myself from cold but after treatment i got recovered but last year i shifted to New Delhi and since then i am suffering from continuous sneezing in the morning daily and nasal congestion but that also didn't cause any problem to me because that mainly occurs in morning time. Now for last 3-4 months i am suffering for continuous cold and sneezing but this continues for the whole day and i can't concentrate on work and for last three months i hardly remember a continuous week when i would've felt completely good. I take medicines get recovered and again fell ill. Doctors says i am allergic to something that they are not able to find before that one doctor said that i might be suffering from sinusitis. My eyes also turns red sometimes. I don't know whether it has anything to do with it but i thought to post this and also a year back i also suffered from hypertension problem but doc had said that, that was because of restless work.

Please help me.