Ok I have a 2008 dodge ram 4.7L. Pulled into a gas station and when I went to leave I noticed my alarm didn't do anything. No chirp or lights came on. So I went to start it and nothing. Not even a try to turn over. Lights and radio all worked. So I disconnected the battery for a few seconds and it fired right up no problem. Still original battery. Noticed the battery gauge needle takes a lot longer to get up to it's normal spot. Could this be a battery going bad or something electrical like with the alarm?

 

Bump bump bump

 

The trucks act very strange when the battery it low or going bad. The best thing for you to do it pop the covers off the battery and check and acid level and add some if needed. If it continues or if the battery is full then go get it tested and check out.