Could the terrible 2's get any worse

Gianna will be 3 in 2 months. I thought we were over the worst of the terrible 2's. No such luck. In fact things are getting worse. Last week was a doozy. Words can't even describe the frustration and sense of despair I ended every day with. Let me update you

Although Gianna is fully potty trained, last week she decided that she would resort back to her baby ways and have accidents anywhere and everywhere. Including a number 2 in the middle of my driveway while we were outside playing. Nice

Wednesday I had to go observe for work so both kids were going to the preschool rm at the school were I will be working. As I was making lunch I heard Ethan's bedroom door close, I quickly packed up the lunches and went to investigate. This is what I found

Both Ethan and his room were a cloud of baby powder. Gianna had gotten a hold of my extra large tub of powder and tried "cleaning" Ethan's room with it. You want to talk about a mess. It was a disaster. Took me hours to clean up

The following day after I sent her to time out for something I found every clothing item and toy she owned scattered about her room

The constant mess these kids make are enough to drive anyone crazy. Add to that Ethan getting sick and projectile vomiting everywhere and myself coming down with a sinus infection Ive come to the conclusion that I'm officially at the end of my rope with this deployment and my kids.

Gianna does not Listen. At all. I've tried everything in regards to her behavior. Spanking, time outs, taking things away, behavior charts, stickers, etc. Nothing has a lasting effect. Nor do they seem to phase her. It's maddening. I feel like all I'm doing with her is yelling. And what mom wants to feel that way day in and day out. I always apologize to my kids after I yell at them. Now thoigh when I have to scold Gianna her immediate response is "are you sorry you yelled at me" am I raising a toddler or a teenager?

I've noticed that when we are our and about doing things such as going to the zoo, pool or at the park Gianna is on her best behavior. It's like the more stimulation she gets the better behaved. But I can't offer her constant stimulation at home. I'm basically a single mom till my husband gets home and I have two kids to split my time and energy. And both fight for my constant attention

Any advice out there? I need any and all the help I can get.