Was my bank account hacked?

Do you know how to do a bank reconciliation from your bank statement? Look at your account online and make sure you have recorded all the transactions that have posted to your account. You could have forgotten something small, or there may have been a service charge posted to your account. You also could have made a subtraction error, or your paycheck may not have posted yet.

If your account was compromised, ie someone got into your account and taken money from it, then the bank would still have records of it.

I then checked my transaction history and the bank said there was no records of any of my transactions - rather confused by this. you checked your history where ?  And then the bank is saying that there was no transactions ?  

You need to go into the bank and speak to someone and sort this out

it could have been a fee monthly assessed by the bank, so yes, spend your time to go in to the bank and show them your evidence and ask