I am sorry you don't have any confidence in your doctors. I stand by what I said before and that is high blood pressure and ADHD have no physiological connection to one another. Your heart rate and blood pressure can be directly connected but not always. People who are ADHD and fidget and move all the time are not driving up their heart rate to any discernible level. I have taken many blood pressures and pulses of people with the history of ADHD and typically their vital signs are within normal limits.
Blood pressure is effected by two factors- volume and pressure. Think of a garden hose. If you put a garden hose on a fire hydrant and turned the water on and measured the pressure within the lumen of the hose you would find the pressure up due to the amount of force on the hose from the volume of water going through it.
If you took a garden hose and twisted it up but didn't occlude the lumen of the hose completely and then put the water on you would find in order to get a strong stream you would have to really crank up the amount of water going into the hose. The pressure within the hose would be up.
Now think of your heart. It is a series of "hoses" connected to a pump. If the "hoses" or vessels are narrowed due to plaque (cholesterol and lipids) then the heart will try to pump harder to force the blood through the smaller opening and lumen of the vessels. This PRESSURE will drive up your blood pressure.
If you have too much volume in your body (usually not the case; usually you lose volume due to bleeding somewhere which results in low blood pressure) your blood pressure will go up due to more VOLUME. (This is one way to treat low blood pressure - give some fluids and get the volume up)
Now, I ask myself "why is a 20 yr. old female presenting with such high blood pressure?" To find the answer tests must be done - blood work first. If that reveals nothing then you go on and start trying to "see" what is wrong through imaging tests. I would suggest you go see a cardiologist. Try to get some answers for this.
It may be due to diet and weight. If that is the case you must find a way to take off the weight. More health problems will result if you don't. You are so young. You should not have blood pressures that high. I am accustomed to seeing those types of pressure on older people who have done some living and had years of build up in their vessels to drive up their blood pressure.
Do yourself a huge favor. Look at this as a warning. Go see a cardiologist. Look at your diet and clean it up. If you quit drinking pop and eliminate sugar and white flour I GUARANTEE you that you will lose weight. Start slow and get rid of pop. The next week eliminate cookies, pastries, cakes. The week after that eliminate white noodles - use whole wheat or whole grain by Barilla. Even my picky little boys eat them! You can do a lot by just slowly eliminating bad stuff and replacing it with good food. Fruit will help with sugar cravings.
Let me know if this helps. I don't mean to preach but you are too young to start on a path of poor health so early. That is for old folks. Save it till you're old and take charge of your health and live. Let me know if you have any more questions. You can PM me if you like. All the best.