I would worry, the thined OIL is not a good thing. You could have a fuel pump that is not shutting off and has flooded the cylinders that had flowed by the piston rings. Was this sitting all night and then you found the issue? The other thing that I have seen is the OIL change shop forgets to put in Oil and then seizes the engine
Worst it could be is that the fuel pump isn't shutting off
I wouldn't worry about the smell, 1995 should have thicker oil in it because of its age. 10w40 maybe.
My oil gets thin like water at around 2k miles and I think its because my carb is dripping fuel into the engine when it is not running. Anybody agree? Disagree?
It means that gas is leaking in to motor need to get looked at soon