Hi there i went through the same problem and it took me along time before the headpain would not start. I started with one step then took thr elevator, I Walked

slowly, even laying in bed was hard. If I thought about about anything that could be a tiny bit stressful i had the head pain
Jo mar's suggestion of slow and steady really helped me. I bought a puzle and would do a couple pieces then would back off, same as talking, walking, computer etc.
Back Off or stop any activity that causes pain or your bp to raise. Im much better now but it's almost 3 years and slow and steady will yield the best results. It takes time but always try until your body says stop.
Hope you feel better
Susan