Skipping your period

so I'm supposed to get my period the first day of finals (May 2nd), which would be a bit of a disaster because I get really bad cramps and headaches, and if I got those and was unable to concentrate I'd be kinda fucked. so have any of u guys ever kept taking your pill (combination) for longer to skip your period or get it a couple weeks later? should I skip the placebo pills and directly start taking a whole other strip or only 2 more weeks, then placebo, then the other week and placebo pills? or just throw those away then and start a new strip after my period??? I'm not sure what is the best way (it doesn't matter if it affects my fertility though bc I won't see my boyfriend at least until June)