B12 with Lipo B

hi, all!  new to the site - lots of useful info.  37 yr old female hoping to lose enough to be a healthy size 6-8.  5'5 1/2, 175 lbs, bmi is 28.8, fat 39%, size 11-13.  I quit smoking 54 days ago and was starting to put on weight (I was already overweight before stopping the ciggs.  Wanted to avoid teh 40lb weight gain my mom had so just started with phys. 7/17.  I am taking phendimetrazine 35 mg 2 tabs three times daily, phys. supplied multi-vitamin, phys. supplied Garcinia cambogia extract and Crhomium dietary supplement 3x daily 1 hr before meals.  I have many questions that I either forgot to ask or didn't think of while at my appointment due to either excitment or simply not knowing what questions to ask. Here's one:  i will be getting the B12 injections each week with the option of either Lipo B and B-6 or both. I will opt for the Libo B each week but am uncertain as to whether I should have both the B12 and B6 (not even sure if they are similar).  Does anyone know the difference between B12 and B6?  Is there anyone that has done all three (B12, B6, Lipo B) in addition to phendimetrazine (or an equivalent)?  What are your results?  Does anyone know anyone that is a long term success story?  Thanks!