Every app I use needs to be forced closed after less than 5 minutes. Even apps I haven't even opened [before]. I've turned off my phone and restarted it multiple times and nothing seems to work. Does this mean I have to do a factory reset?
• First is make very sure you've free space of memory. My One Plus handset makes this behaviour when it is near to 'out of storage'.
• Second is make sure you have not deleted any root directory by opening file manager with some specific app explorer. (This might create problem as once i meshed up with those folders and end up tolerating crashes.)
• Third is the last option do a factory reset .
This sounds like a file permissions issue on the data directory.
The only fix would be to wipe, however if rooted and/or have a custom recovery, you should first try the fix permissions option.
Otherwise, you will have to do a factory reset.