2003 rodeo, V6

I started out trying to simply install a new battery and completely went off the rails. I first connected it backwards so there may be residual damage from that. I have it correctly connected now, and systems seem pretty normal except that it doe'snt start or even crank. the key fob operated before, fine. Now it causes the same sounds(horn beep, once for lock, twice for un-lock), yet the locks do NOT actually engage or disengage now. Fob panic button DOES activate and deactivate panic mode but no other functions operate. Have attempted several varieties of solutions and am hoping this is a case of needing to know the proper sequence of things to reset the immobiliser. turning the key to the on position and back to the "ACC" position three times causes the horn to beep thrice. This probably is an indication of something, perhaps a step in the phantom "sequence" but that is only speculation on my part. I have all dash indicators lit up when key is in "ON" position. Turning key to start position results in nothing. Just bought two days ago and everything was peachy until I wanted to put the new battery in and I screwed that up royally.
Please advise.