Santander Issues, Banking Woes, Destroying the Students?

Okay, I accept at times I have become a little overdrawn in my santander account, and I have made my peace with the 25 pound charge for being overdrawn. But what I was shocked to find in my statement charges being added for purchasing items whilst being overdrawn. Having checked back through my statements dating from yesterday all the way back to November, I found I had been charged numerous times for these 'paid item fees'. Having taken up the problems in my local branch, I was informed that the charges were all part of the account, fair enough. But my issue is that I wasn't made aware of any charges being applicable to my account where I to become overdrawn, I only found out I could become overdrawn having had the account for nearly 2 years, and the additional charges (paid item fees) have only come to light within the last 48 hours. I told the very......helpful....... member of staff this issue, but was told that as I couldn't remember the name of the person who opened my account (3 years ago, I was 15 and didn't think to ask) that it could not be proven that I wasn't made aware of such charges. The money equates to around a months wages for me, and in this time were everyone is feeling the squeeze, including the students, losing that kind of money doesn't bare thinking about. So my question is, as I was not made aware of such charges on my account, do I have grounds to claim the money back? I was told that I could claim one 'paid item fee' back from the 4 month period. There are 15 seperate ococcasions in which 'paid item fees' had been applied, and the maximum was only 15 pounds, it doesnt seem particularly worthwhile. Had I been made aware of such charges, I wouldnt be posing this question.