Terrible headache

I have had a headache/migraine for well that went on for four days. I "think" I have figured out why. The Avastin that comes with the chemotherapy treatment gave me high blood pressure and guess who has not taken her high BP medicine for awhile??? So, I just have been taking my blood pressure and it has been high so started taking my blood pressure medicine again about 3 days ago and yesterday and today no headaches but pain in my head when I laugh, cough or sneeze.  And now I can't sit up for a time without my nausea.  I am tired of this never ending it is always something and just give me a week or two with no  pain or anything anywhere, please.