should I go to the doctor? o.o

So, I went to take a leak today and after pulling my pants up, my vision got darker and I felt light headed then fainted, when I got up I found that I fell faceforward on the floor, had a really painfull bump on my forehead. afterwards I dizzily stumbled to my bed and just spoke to my gf for a few hours. however after a few minutes I noticed that the left side of my neck,left shoulder,left arm all hurt ... sorta like needles. (p.s I fell to my right ) (p.s I felt abit of trouble breathing and fast heartbeat before I fainted )

I don't know why it happened maybe some of you are abit more knowledgeable , I'll just list what I did today.

went to sleep at 8:30 AM ( couldn't fall asleep after, had to reflect on an important conversation )
woke up at 2:30 PM and spent 30 minutes making lunch ( chicken salad )
3:30 spoke with my GF till midnight
Midnight went to make a sandwich ( mustard,pastrama,lettuce )
5 minutes past midnight till 3 AM kept talkin to my gf
3 AM went to take a leak and fainted.

thats basicly all I did today. maybe its from barely sleeping, I don't know.
going to the doctor isn't a money issue I just don't want to go if its probably not nessisary and worry my siblings.

when they heard the boom of me falling onto the floor ( its made of marble ) it woke everyone up. I just told them I slipped.