HELP PLEASE?!

So my boyfriend has finally gotten me up to the point where I have enough confidence to go to the gym and work on my body. I haven't been going for a very long time just basically whenever I'm able to so I've probably gone about a few times since I started working out. And my brother has wrestling practice tomorrow/later today so I'm going to work out while he's at practice before I have to go pick him up. But sadly... I just now started my period.. nothing extremely heavy at the moment but is also slightly unpredictable since, within the last 3 months, I have taken Plan B with my boyfriend so it is still messing with my period. Any tips for when I go work out?!?!?!