MRI and Elevated Prolactin

My endocrinologist recently ordered a lot of blood tests to help figure out what is going on with me.  I am 29 years old, in the last year have gained 40 lbs when I have always been very thin and recently diagnosed type 2 diabetic.  I have purple stretch marks on my thighs, but no new marks on my stomach.  I itch a lot and have headaches. My vision has decreased and occassionally feel like it's slightly tunneled.  I get dizzy frequently.  

I had a child in the October 2001 and breast fed until November 2002.  I saw my gynocologist in January of 2007 with complaints of continued lactation even though I hadn't breast fed in over 4 years.  I was also having problems with ovulation pain and irregular periods.  They perscribed me birth control pills and ordered a series of test like TSH, Free T4 and prolactin.  I began the birth control pills and the lactation stopped.  I didn't equate that beginning the birth control pill was related to the the halt of lactation until about a year later.  They ordered the tests again and prolactin was normal.  My endocrinologist however suspected that I needed to be off the pill and take the test again.  After stopping birth control for 4 weeks I took a very detailed blood test and my prolactin levels were 50.5.  Lactation hasn't resumed, but my periods are irregular and my breasts are tingley, like it may begin again.  My dr. has ordered an MRI with and with out contrast.  I haven't gone for it yet...  Below are my tests (condensed some, due to how many were taken, if you'd like for me to type them all out for you, I can).  If you could help me with figuring them out that would be very helpful.  I have indicated with an H the ones that came back high. I have read a lot of articles and have found very few on the causes for mildly elevated prolactin.  I guess the MRI will tell more, but it's still helpful to have a medical opinion of what my dr. is looking for... some other possiblities than the normal prolactin secreting tumor, since my prolactin isn't really high...   Thank you in advance!

ACTH 12
creatinine, random urine 422 H
AST 40 H
ALT 67 H
Thyroid Peroxidase Antibodies 42 H
FSH 3.9
LH 13.3
Prolactin 50.5 H
T4 Free 1.1
TSH 3rd generation 4.55 H
HCG Negative