I cleaned the inside of my computer today, and now it's twice as loud, any idea why?

I opened it and blew compressed air everywhere and then went nuts with Q tips cleaning it, especially the three fans.
(Except the power supply fan, since I can’t take apart the box.)
Now my computer is like twice as loud as before…my bf says it’s a difference between dirty and clean fans, but shouldn’t it make more noise when they’re all dirty due to them struggling?