Go to the project folder and clean up Binaries, Intermediate, and Saved. Especially Binaries, it gets ridiculously large very fast.
You can actually just delete them completely and then launch your project (the first time it’ll have to rebuild, which may take up to several minutes), and it will also reset your editor interface changes back to default, but that shouldn’t really be the issue.
I generally just go to Binaries and delete all the files that weren’t created/updated today (except for the last .dll and .pbd that have no number next to them). It seems to help a bit with compilation times.