Girivenkiteela,
I applied last year in July (around the 20th) and I saw others on this forum who applied around the same time. Some got their visa well in time or in late August, others got it just in time during the first week of September, some got their visa a few days after their college start date and were allowed to start a little late. I got mine 4 months later. It varies from case to case. I know it is easier said than done, but try not to worry about it and relax. Good Luck!
p.s. I worry that telling you that my application took approx. 4 months to process last year may depress you a little. I probably had a complicated case. You have just as good a chance as anybody of getting your application processed in time. Stay positive.