I turned on to Baed leg and had lost sight of the Cessna in front of me
Most important lesson I think is NOT to turn base when you are number 2 and have no idea where number 1 is.
You can always ask ATC to call your base turn for you. They will then inform you when to turn base, and ensure sufficient separation between you and the number 1.
Anyway, did you debrief this situation with your instructor? Sounds like an excellent learning opportunity. Particularly if you can follow it up with a visit to the tower, speak with the ATC on duty and maybe even review the radar tapes.