I'm on 4mg zofran in the morning and again mid afternoon.
The headaches and light sensitivity I got before starting the zofran and really taking it super easy (I was trying to push through it, until that no longer was an option). I think it could be tiredness related? Can you rest more (Ha ha. I know it can be hard).

Also, I've starting eating all bran twice a day (lukcily I can stomach it if I eat it while watching TV to distract myself)- fibre tablets didn't do anything for me, but allbran has me back to once per day (TMI!)