Question Circle stops spinning on profile load

That loading circle that shows up on booting the PC stoped rotating. I couldn't load into it. After shutting it down and restarting it. Then I went into safe mode. This allowed me to access this profile. I switched user to my main user and restarted. This time around it booted without much problem. Later today its happening on my main profile and others as well. I can't log in to my PC at all. What could be causing this and can I fix it myself?