Don't be sad.

I took GRE and wanted to go to school for PH.D, but I could not transfer H4 to F1 afer we applied for our green cards (EB3). I had to change my major. I went to school, but I had to paid for my tuition. I am still taking courses now.

We did not give up EB3 application even though my LG was qualified to applied for EB2 because we did not want to waste our money and time.Instead, I applied for my EAD with I-485 receipt. I had a part-time job while I took courses. Now we got our green cards finally. I think that you will be OK if you have I-485 receipts.

Cheer up! Good luck!