Hey dear, cutoff varies every year, if you see the last year's cutoff which went very high that even students getting 500 marks were unable to get govt. Mbbs colleges. Since you are expecting 518 marks and under general category ypu have good chances under state quota, but no in AI quota, just stay tuned to counselling. You can also predict your college through this link:

https://medicine.careers360.com/neet-college-predictor?icn=QnA&ici=qna_answer