Hey.

You can use this Rank Formula to get an estimate of what your rank will be around    (100 - your total score) X 874469 /100. Here 874469 are the number of candidates that appeared for JEE mains 2019 January attempt.

Hence considering your percentile and using it along with the formula, you can estimate that your rank will be around the range of 306, 000 in the general merit. This is  only an estimate. It might differ also because the final rank will be computed on considering the performance in both January as well as April Session. You seem to have a fair chance to qualify from the SC category.

Best of luck