What should you do if you have been starving to lose weight and have lost 11-12 lbs in the last six weeks and now your blood pressure has gotten very high?

You will end up in the hospital. Starving yourself to lose weight is not the way to go. It is unhealthy and your doctor can put you in the hospital for it. If you start eating healthy, drink lots of water and exercise your blood pressure will start to go down and you will become healthy again. (What works for me, is eating every 2 hours because that's when your metabolism is at its highest and you don't eat huge portions)