My Ex is changing my Sons Schedule that was working - He doesn't want to - What do I do?

14 months ago, my ex wife emailed me to tell me that she wanted to change from our son staying with each of us in a split arrangement, her house one week, my house one week. To a situation where he stays with me durring the school week and she see him everyother weekend and visit with him one night a week. We swap the situation durring the summer months. This was all due to his behavior at school was becoming un-manageable and he was not behaving at her house either.

We have been opperating under this agreement now for 14 months, and my son is doing very well. I approached her 3 months after this agreement was in place to ask if I could now stop paying her child support, I didn't want any support from her, and infact also offered to pay for day care + his health insurance, and that we alter our decree to reflect the new arrangement. She completely blew up and became irrational about my request. So I agreed to just keep paying her.

Now that it has been 14 months my wife and I have decided that enough was enough, (especially after she filed her taxes and claimed him as a dependant - when it isn't her year!!). So we hired an attourney and filed a motion to modify. After getting her copy of the filing (which asked for nothing more than to change the parenting plan to what the current situation is) she has totally freaked out. And is forcing my son to stay with her one week at a time.

My court date isn't for another 4 months. My attourney sais that I can't really get a temporary hearing because juges don't want to hear cases twice. If my son lives with her 50% of the time again for 4 more months, will I be faced with doing myself harm for filing this motion?

Tell me the world is not this unfair?