Illustrator half-frozen when using blob brush; can change tools and make marks, but they don't appear on screen until I save+close+reopen file

So a really weird thing has been happening. I'm running a brand new Windows 10 machine, and recently I've had this strange issue where Illustrator is sort of half-freezing. Basically, I'll be drawing a (very simple) illustration with the Blob Brush tool. Halfway through the line, it will freeze. I get about 10 seconds of the spinning loading wheel, and then everything about Illustrator unfreezes except the canvas. This means I can change tools, and click/draw/erase on the canvas, but nothing happens. When I save the file and reopen it, anything that I did blindly while it was "frozen" is there. So if it were to go into this half-frozen state and I drew a circle, even though it wouldn't show it when I drew it, after a save+reopen, the circle I drew would be there.

Does this make sense? I have no idea why this is happening. Only happens sometimes, the files are never big, usually just sketches or linework. I work on much heavier/larger/more complicated files all the time and never have this issue. It literally only happens when I'm trying to use the blob brush.

Please help!