A candidate gets a maximum of two attempts in consecutive years to appear for JEE Advanced.But as you have appeared the advance in 2016 you are entitled to appear it this year.There is no age limit present know ,so you need not worry baout that also.

I would suggest you to prepare well .I hope this help.Best of luck.

You can apply with a new mark sheet and the previous count doesn't affect this attempt because use used new 10th and 12th mark sheet so everything is new to make a better attempt for you and get your dream college which you dream from starting your preparation.

All the best Manish