Reboot it. Apparently that’ll make it run at full speed again. It rebooted after I entered an unlock code. So either rebooting, or unlocking it made it fast again. Think I’ll setup Tasker to reboot my phone at 12 am everyday.
Might not be a good idea. When it’s booting back up, it’ll make a sound, which might wake me up. Guess I’ll reboot it when I feel like it then.