fainting feels weird!

so, my last 2 pregnancies i get really dizzy if i get up too fast. the other morning, brian was shaving in the bathroom, and i was laying in bed not wanting to get up. the urge to use the restroom came on strong (which happens quite frequently these days) so i hopped up and walked into the bathroom. by the time i got in there, however, my vision was already gone, and my body was shaking uncontrollably. brian thought i was doing a crazy dance to make him laugh, until my head hit the wall pretty hard, and the rest of my body began to crumble. thankfully he was in there, because he realized something was wrong, and caught me underneath my arms until i started to come to. it really is the weirdest feeling- i don't know if i am the only one, but my sight goes black, and i shake, and can't control anything. when i was pregnant with makenzie, it also happened, but i was alone with the kids, and i hit my head on a corner in the bathroom and ended up having to get a couple of stitches (my first ones ever, besides the csections!). anyways, i am sure to get up slowly now- i don't want to faint again!