How I feel on Adderall. Too early to tell if the dosage is right?

[addicoe]

First of all a little about myself. I was diagnosed with ADD when I was 5, then re-diagnosed with ADHD-PI when I was 15. I took medication from 7-15 years old. I have taken Strattera, Ritalin, concerta, Adderall IR, and Adderall XR. I stopped taking them when I was 15 since I didn't like the stifled creativity and feeling of tunnel vision. I was then free of them through the rest of high school and all of college until now (I'm 22). I started a new full time job, my first one out of college and was having trouble getting my work done on time. So this week I started taking Adderall XR 20mg once a day to help me. My goals by taking this were to get mental clarity (get rid of the foggy feeling) and also increase my thought process (increased focus was not what I was most interested in). So far I've been on it for 3 days and this is how I've felt:

-very decreased appetite
-very noticeable feeling like a pressure in the front of my brain, like someone is grabbing the front of my brain. This goes away a while after the medicine wears off but seems to take a long time
-no increased memory
-slight increased ability to focus
-no clarity in the head (instead the foggy feeling was just replaced by the pressure feeling)
-no increase in thinking speed
-slight increase in heart rate
-more difficulty staying asleep (I woke up at 4:45 AM yesterday for no apparent reason)
-easier to fall asleep quickly
-not able to tell when the medicine is worn off (it feels like it's always working, the only time I feel like it's worn off is when I wake up in the morning)
-feeling more tired than usual when I wake up in the morning

by the way, I have been sleeping around 6hrs a day
The pressure in my head and no clarity is what is really bothering me, since that's what I wanted most. From what I've read the pressure could be because I'm not drinking enough water, eating enough or getting enough sleep.

About 3 months ago I had started taking concerta 36? mg once a day and the first day I took it I felt amazing. I had a super clear head, was able to think really quickly, and I had that euphoric feeling. But I only got it that first day, and never again after that. I actually felt like the medication wasn't doing anything after the first day.

So my question is: Is my dose too high, too low or is it too early to tell? If I keep taking the Adderall for a week will I eventually get the clear head I'm looking for? Or is Adderall only going to give me more focus? (which is totally useless if my brain can't think clearly or think faster).