Hi, 

It actually depends entirely on you.

Its not a hard and fast rule that you have to make it through the entrance in d very first attempt. There are students who try for 4-5yrs before they finally crack it.

It all depends on ur determination nd ur willingness. If u r ready to work hard all over again with d se consistency and vigour.. Definitely try for another year. But ONLY if you feel that you can do justice in that one year and won't get upset or depressed by seeing people around you.

But if u are having doubts then taking a drop wont be of that use.In this case i suggest you shuld join some college. Try for private/deemed universities if ur marks are above the qualifying mark. Or u may look into other streams lik B.Sc,BA,BBA etc..

All the best