Yes, I'm a bit concerned about your pot solder joints after looking at the pics more closely.

I always sand the back of the pot first to remove any oxidised metal, then run solder on the back of the pot. It needs to be got hot enough so that the solder melts and spreads out over the back of the pot. Then tin the wire for the connection, and then make the joint. Again, it needs to be got hot enough so that the solder melts properly and spreads out, and doesn't remain a blob that's lightly tacked to the surface as it's likely to come off in the future.