I Am Having Painful Headache Like Symptoms. My Head Feels

I am having painful headache like symptoms. My head feels like its an overstuffed balloon ready to pop. When I bend over or exert pressure, I have extreme pressure pain. I have been feeling occassional nausea; no vomiting though. No fever, Blood Pressure is always fine - or low. No dizziness. I first started getting these symptoms after having a TAH BSO. I was on hormone therapy using Premarin for quite a while. I am mentally disabled and medicare has decided not to cover hormonal treatments. I seriously need something! I had my hysyterectomy in 2002, I am a 54 yr old female. I have a pacemaker due to sick sinus syndrome.