Hello Bhargav,

No worries you still have a chance, 

In Sastra university, 70% seats will be filled based on JEE Main 2018 scores of the candidates along with 10+2 or any equivalent examination normalized scores and remaining 30% seats will be filled based on candidates' 10+2 or any equivalent examination scores (after normalization).

Please check the below link for more information:

https://engineering.careers360.com/articles/sastra-university-btech-eligibility-criteria

Good Luck!!