i can't edit or move any of my audio or midi tracks in the arrange window

its the weirdest thing.

i've been working in Logic all day, about 5-6 hours now, and everything has been working great,

i left the room, for no longer then 2 minutes, and now all of a sudden, i can't move any tracks around... i can't click on any of my tracks, and the only way for me to highlight tracks is to drag the cursor across them.

i can open my piano roll to fix midi, but even when i do that, the midi will disappear when i hold the click to move it (so i have no idea where that midi is going)

i've closed and re-opened, and the same problem is happening in all of my projects.

someone help?