Hello Dear,

Based upon your score in NEET 2018, and the previous year cutoff, chances are less for admission to Government Medical Colleges under All India Quota and state quota. You may have chances in Deemed Universities. Use NEET College Predictor to Check Your expected MBBS/BDS colleges based  on Your NEET AIR

https://medicine.careers360.com/neet-ug-college-predictor?icn=neet-clgpd&ici=qna-answer

also, check previous year cutoff of Tamilnadu:
https://medicine.careers360.com/articles/neet-cutoff-tamil-nadu

good luck