Can I call in sick today even though I am not sick whatsoever?
Are you trying to take some time for yourself?
I feel like I'm 100% fine and I wish to do whatever the fuck I want to do
It is wrong to be dishonest with your employer. If they sense you are not honest they may fire you.
Bullshit. They do not have concrete proof even though I know they can fire me on the spot.
If you are experiencing burnout from work, then ask for some time off instead of feigning a sickness. You don't want to risk losing your job over a small little lie.