I had sex the day before i start ovulating (according to my period tracker) and i took plan b right away. will it still work even if i'm ovulating?

Probably yes: Most likely yes. Plan B has a high dose of progesterone that makes the uterine lining incompatible (for that month) with a potential embryo. There is a small failure rate with Plan B. If your period doesn't come on time (+/- 3 days) then check an over the counter pregnancy (urine) test.

Yes: Taking Plan B right away maximizes the chances that pregnancy will not occur. Using birth control pills are a more effective way of preventing unwanted pregnancy. Also, having unprotected sex around ovulation is a good way to become pregnant. That's what couples do who are trying to conceive (TTC in current parlance.