In the normal course of things relative to pitching competitively, this is not all that unusual. In fact, this happens a lot with off-speed and change ups.
Here's the chance to recognize one of the routines that'll serve you well as you compete in this sport, especially as a pitcher. And that is ..you mentioned one important thing that is a credit to your awareness and your excellent attention span - "My Changeup has been awful lately not spinning and staying hung out over the plate"
This remark indicates a benchmark, or reference point, that you witnessed something that heretofore worked - or I'm I assuming something that's not true? In other words, there is something different happening that wasn't there prior to this current situation?
So, think back to when you decided to use your changeup, how you gripped it, how you prep'd yourself prior to...during... and after your release. What's different about you, and why? Is your concentration the same? Are you going through any emotional issues - personal/social/family? How about your relationship with coaches, teammates, umpires, hecklers, and so forth.
I should mention that a changeup is just that ... a change from the speed/velocity of a PRIOR pitch. In other words, usually that PRIOR pitch was a fastball, at your fastball game speed... nothing held back, your best stuff fastball wise. Some pitchers will mistakenly use a pitch called an off speed by tossing a floater, just to maintain control and thus, that pitch plows right through the sweet spot zone of the bat.
The terminology between an off speed and a change up is not something that I'm going to expand on here, but, just be mindful that if you're trying to alter the incoming speed of every other pitch to upset the batter's timing, your concentration of doing just that, and not maintaining your normal delivery mechanics, could be your problem. It's kind of difficult to advise you accurately and in a meaningful way, without some sort of video - especially from behind your backstop (catcher). The only reason for my suggesting that vantage point, is because I used that visual witness during my coaching years to evaluate off speed pitches with varying incoming velocities, and locations. Others may prefer other vantage points so please address their requests also.
Finally, the pitch(s) that you're trying to master is one of the most difficult pitches to bring in your bag of tricks. It takes years to properly develop, choreograph your "selling it", and when and when not to use that pitch(s).