weird symptoms or normal?

All of my vitals have been really good. I'm 4 months pregnant. My memory is so bad these days it's almost scary. My vision is not nearly as good and I see waves in my vision when seeing in  bright light or looking at white or light colored  things. I always had floaters in my vision but lately they've been really severe. I twitch or one of my limbs lightly jerks sometimes when I'm relaxing. Is this all a part of pregnancy or do I have some other disease/disorder/complication/cancer/tumor going in? It's been eating at me