short somewhere?

70 Duster. I disconnect the battery when it sits. Noticed lately that there is a very small spark when I connect it back up that I did not notice previously. I am still learning electrical stuff, so not sure if I am using my Flukemeter correctly or not. I disconnected the - batt terminal and when I connect the meter probes between the batt and connector the meter starts at about 16 and rapidly works it's way to 0.5. Is this the way the meter would normally read? Without hooking up the batt, if I let it sit for a couple minutes and do it again it reads the same.
I tried to upload a video of my meter as I do this, couldn't so am trying a uTube link. It takes about 10 seconds in before I get a good connection.
Thanks