What is wrong with me mentally?

For the past couple months, i've had recurring depersonalization (feeling disconnected from my body), and it kinda throws off my depth perception. It always starts in the afternoon and ends at night, no matter where i am. Whenever the depersonalization starts, i am hit with severe fatigue, i get very lethargic and struggle to keep my eyes open. A couple times i've had weird racing thoughts that made no sense whatsoever, i can't even remember or make sense of them to give an example. i'm also getting very bad bruxism (urge to clench/grind teeth. When my depersonalization fades, so does the urge to clench so i think they are related somehow. My short term memory has been getting increasingly worse. i'll be walking into a room and forget why i was going there in the first place. i'm having a hard time remembering certain phrases and words. At work today i almost misplaced certain items while walking to put them away, but i caught myself before hand and put them where they belong. But that never happens to me. i'm starting to get really scared, i feel like maybe i'm going crazy. i have no medical insurance and literally no money to see a doctor/psychiatrist. What could this be? Is there any way to prevent the depersonalization? And why do i feel so extremely lethargic when it hits?

Other info that might be helpful:

*i'm 20 years old

*i had my first child a year ago, immediately after his birth i was diagnosed with Post Partum Depression

*i take 20mg of Paroxetine (generic equivalent of Paxil) every other night

*i'm always stressed

*Also not sleeping well. i can easily fall asleep but cannot stay asleep

Can someone please help me? Has this happened to anyone else? Were you able to get it diagnosed and fixed? Is this possibly some kind of neurological disorder?

i'm just feeling off/weird in general. i feel like something is definitely not right with me. i feel out of it half the time.