Hey fnfgopro,

That definitely sounds like a plateau! 

Maybe it could help to change things up. 

1 - Have you tried, or are you able to have a jam session with friends? Even if it's a 12-bar blues jam, that can help a lot with getting into a "flow" with your playing. You could picking something really simple, just one or two chords (something that doesn't require "thinking"). Looping it for a while without any judgment can help break through that. Even if you're just playing root notes (so you don't need to worry about full chords), you could try being in a more "fun" mode instead of getting stuck in only the analytical (which also has its place!). 

2 - You mention tensing up. Does staying on one chord give you the same problem? Is it a right-hand or left-hand tensing-up issue? Or just a general "nerves" / blanking out thing?

-Carl.