Car Alarms: 1993 Nissan Pathfinder, nissan pathfinder, security switch

Question
I recently purchased a 1993 Nissan Pathfinder.  It runs great. And everything seemed to be fine until.... I made the BRIGHT idea to replace a blown bulb in the overhead light and replace the missing fuse for the horn.  I accidently put the wrong size fuse in the the horn stop but removed it when I noticed my mistake (in less than a minute).  I finished with the overhead light and checked the cargo light which also wasn't working.  It came on briefly then went out ~ I thought that it just needed a new bulb.  So I replaced the old bulb and picked up my mess and went inside.  Shortly thereafter I realized that I had a problem when the alarm went off.  After trying everything that I could think of to correct the problem I finally disconnected the battery cable, thinking it would reset the alarm and all would be fine.  NOT THE CASE.  Upon reconnecting and closing the door the alarm went off again.  I have tried everything. replaced the security switch(nothing happened ~ even when the switch was totally disconnected), changed the bulbs checked for loose wires and haven't been able to correct the problem.  I finally found the alarm box (I think) and depressed the reset button, nothing happened. I've checked all the relays I could find and they all seem to be working fine.  I finally traced what I think to be the power source to the battery from the alarm siren and nothing changed it still went off.  I'm lost, PLEASE HELP.  It I could find a way to disarm the system I would but I can't locate the hot wire as yet.  After things went stupid, while driving the interior lights came on upon taking a sharp curve.  I'm PERPLEXED and would greatly appreciate some help.  Thank you in advance for any light you may be able to shed on my problem.  
Sincerely,
Michelle Mandrona
BROKE ~ SINGLE MOM OF 3

Answer
Please be more descriptive if possible.

"GOING OFF?"

I need to determine whether it's a factory alarm
issue or, if it's an aftermarket system you are
dealing with.

Is it: Headlights flashing, car horn honking
and a worded SECURITY" light in the dash flashing?
(doubtfull since none of the notes show this
car as having a factory alarm system)=FACTORY

Or,

is it: flashing parking lights,
an LED in the dash area, and a siren
going off?= AFTER MARKET

Let me know more on this to better
advise you on a course of action
to take.

Best Regards,

Robert Martin
CEO/ALARMTEK
CARALARMMAN.com