2000 Nissan Xterra Brakes lights stay on

Yesterday my battery went dead but not your typical dead batery, battery was less than three years old but I live in Souther Hot Florida and thought the life is shorter than the Midwest. Yesterday after work the battery barely started the car this morning totally dead no clicking, lights or nothing thought I left something on. Put a new battery in and the Alarm system started went off, I have never used the alarm sytem, bought the suv useed 4 years ago and did noth ave keyless key either. After the horn and lights flased I went over to the car put the key in the door and the alarm shuit off but the three brake lights now stay on, I think this started yesterday, maybe that is why the battery was dead. I disconnected the battery first negative and reconnected then positive then reconnected but the brake lights stay on. If I remember correclty I think the red alarme indicator inside is always on but never have had a issue with the alarm really did not knew it existed until today. I disconnted the negative cable tonight before I went to bed so the battery would not be dead in the morning. Thought about looking for the fuses, their appears to be a larger separate fuse books that handles the alarm and pull the alarm fuse to see if they would solve the issue. I appreciate you help.

jrex