Menu Item Limit in Pro?

Hello, I was under the impression that there isn't a menu/drop down button limit in the Pro version (part of the reason I updated to pro.) I recently installed my pro version, and all of the menu navigation stopped working correctly. Then I went into Customize > Navigation- and assigned the correct navigation menus. Which seemed to make it work. Then I realized that a few of my pages were missing from the menu, and now, it's not working again. Is there a limit? Or is there some sort of bug. My site is: https://ieo.wp.d.umn.edu/ I'd send you a screen grab too if you need. Thanks, Sbartsch