I'm freaking out.

I'm 28 weeks pregnant with my second child, and I'm really excited, but now I'm freaking out.. I've recently started watching a friends daughter who is 3. She's not potty trained, she cries ALL the time, she's mean to my son, like will hit him, kick him, etc. Anyways since watching her my son has been regressing. For example he's been potty trained shortly after he turned one (I didn't force it on him) and since she's been around he has started peeing his pants, peeling during nap time, and at night. He's started crying alot more, and he's starting to hit, kick, and spit on people. I don't allow this behavior, and they both get chastised for it. but By the time her mom comes and gets her my nerves are so fried that I can't handle the crying much more and am ready for bed time at like 6pm. I'm so afraid I'm not gonna be able to handle 2 kids of my own..

I'm. Freaking. Out.