Hi! Are you drinking enough? Sometimes (along with a dose change) it's a simple matter of increasing fluid intake...give that a try and can you reach the doctor in the morning on Monday?
I too had headaches while on Suboxone. Speak with your doctor and let him/her know what is going on. It may be as simple as adjusting the dose. It was for me.
Hope you feel better soon. Let us know what the doctor said.