Not going to sleep mode when lid is closed

I recently updated my A1278 to High Sierra to get Microsoft Edge on it (don’t ask) and lately I’ve noticed the thing wouldn’t go to sleep when I closed the lid. I haven’t done anything but update the software.. I even tried holding a magnet over where the sensor should be, nothing. I tried an SMC and NVRAM reset, nothing.

I’ve also noticed the SIL is dim (unless it’s starting up, to which it’s perfectly normal). Sometimes when I select “Sleep” from the menu and then close the lid the computer will instead come back on!

When it does indeed go to sleep with the lid closed, the SIL is very dim. Ironic how I just commented on another thread from someone else having the same issue and then I get the same thing.

What is happening with my computer? It was perfectly fine few hours ago!

Edit - the SIL brightness changes depending on how far I open the lid. I really have no idea what is happening with my computer now.