I Had An Eye Exam About 5 Or 6 Years

i had an eye exam about 5 or 6 years ago and i had 20/20 vision. now i am 24 yrs old and i have a hard time seeing at night... i can not tell the distances between object or other cars until i get close. i also primarily work on a computer and i will be doing strictly online classes. i start getting a headache and get dizzy and find myself squinting at the computer screen constantly. but i see good other wise. do i need glasses?