Hello ajay,

According to me

4th September, 2020 the first shift was the toughest of all shifts. Both the maths paper and physics paper was really tough.

9th Jan Shift 2 was toughest as the tough topics from subjects were appeared  and also there were many time consuming questions  in them , this made the paper more tough in the examination hall.

Next to this, 7 jan shift 2 is also considered as the tough time for students.

Here's a link for your college prediction

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Hope this helps.