How long before I can start doing this again?

You can certainly masturbate during your periods. It’s not going to harm anything! I have heard that masturbation during and right before your period can mess with it a little because orgasm causes uterine contractions and blood is diverted away from the uterus to the more external sex organs (to better help with sensation). But it’s not going to make you sick, and it’s not going to ‘ruin’ your period or harm your body in any way.

First periods are almost always weird. Your first few will likely be irregular (as in, not 28 days apart- maybe several months in between periods), and will be sporradic as far as blood flow goes. Eventually you will stabalize and you’ll find that your first day will be your heaviest (or, the END of your first day will be your heaviest) and you will have a decrease in flow until the end.

The smell is normal, but tampons can help with odor control. If you’re using pads, change them as soon as you bleed, don’t wait until it’s heavily used- change it immediately. It’ll last for a while without leaking, but if you’re concerned about hygiene and odor, the more frequently you change them, the less chance they’ll build up an odor. Make sure you’re wiping completely too. Use tp then use wet wipes- those can really help.