Better to run sooner than later. Disk Utility is written by Apple. Why are you worried. You should have a full backup of your system.
See this article. Pick diskutilty. Run disk first aid.
I read were many people do not recommend running CleanMyMacX. Could be why you are experiencing problems with your machine. I recommend you stop running CleanMyMacX. Read manufacture's site on how to uninstall. See:
Simple put, Apple attempts to provide all the malware detection and removal you need in Mac OS X.
"Effective defenses against malware and other threats" by John Galt
"Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams"
"MalwareBytes Anti-Malware for Mac Removes adware and malware Revives your Mac." MalwareBytes has a more restrictive filter for adware than Apple. MalwareBytes has come to be accepted as the only malware detector you should consider. For those pestered by browser attacks consider MalwareBytes.
Run etrecheck. The first five runs are free. Provided a report on your machines hardware and software. Great for diagnosing your system. Click on the download link at the bottom of the screen.
Apple on Security:
"fake" panic warnings