I had very same thing and it was because my blood preassure was low. I found out from the hospital that this was because i wasn't taking in enough fluids. I still get it if i haven't had enough to drink. This was one of the last side effects to go away for me, but i think if you make it a point to drink more water it will help. I know with everything else you have to contend with, getting your 2.5ltrs as well is the last thing you're concerned with.
Sometimes for me i would completely black out with those fuzzy spot infront of your eyes for 30seconds or so. There was one time i got up to go to the bathromm an ricocheted down the hall off the walls before falling on my knee's scaring my family witless!
It will ease up Allan! Try drinking more.