Air carrier Flight Attendant reported discovering a pressurization malfunction had occurred in flight after the aircraft had arrived at the destination gate where several emergency and company personnel were waiting. The Flight Attendant reported there was very poor communication with the pilot crew.

Narrative

I was the FA on the flight and was working with Captain (CA) and First Officer (FO) from ZZZ1-ZZZ. We landed in ZZZ and as I opened the Main Cabin Door; I was greeted by about six people. One from Rescue asked is everyone alright?' I said yes why? He said we had [requested priority handling]. I then noticed fire trucks beside us. I had no idea about anything happening until the flight deck door opened and then I heard some things...I was then told that we had a pressure issue and we had [requested priority handling]. To my surprise; I was taken back and waited until I could talk to the Captain after passengers deplaned. We (passengers and I) didn't have any indications of a problem and O2 masks did not deploy at any time during the flight. A few passengers asked why the fire trucks were there and I could not answer them. After everyone was gone and the Captain was off the cell and did paperwork on the aircraft; I asked him what happened. He told me we had pressure problems during the flight and that they had to [request priority handling]. I asked him why I wasn't informed of any of this and he apologized and said he was sorry. He said he was too busy..."