Alarm and Radio?

Hi I have a Ford Fiesta 2001 make, and a few weeks ago, our car keys got wet, (our daughter fell into a pool and we had to dive in to save her). Then the alarm went off and we disconnected the battery, but after reconnecting the battery, the alarm still went off, and now the radio's gone.
The alarm horn goes off for a few minutes, but the hazards stay on for a lot longer but then stop. After a week or so, this stopped, but last night, the alarm went off again, and it goes off every time you open a door. Can we do anything?