What kind of issues are you getting? There's a thread here that might help you:
http://7sage.com/discussion/#/discussion/1178/is-your-video-player-not-workinghtml5-error
Definitely circle answers on your test booklet. It may slow you down a few fractions of a second, but if you do mess up your bubbling, you can quickly go back and find where you got lost and correct the error.