Fixing this would involve disassembling the door from the inside (removing the door card) to reveal the workings inside. From there, you can assess whether the glass has jumped out of the rail that supports it at the bottom, or if there's some other problem with the mechanism.

If it’s the former, you’ll need to find out what adhesive is required to fix it back into place. A windscreen replacement specialist might be able to provide this information. A Nissan dealer may also have the correct product on the shelf.

Replacing the glass might be a bit fiddly as there's a lot of gear inside a modern car door, including the side-intrusion bars, the window winding mechanism and the metal parts of the actual door. Some patience may be required.

If the problem occurred immediately after you replaced the carpet and seats, I’d say there’s a very good chance you’ve unclipped a wiring plug or connector to remove the interior, and failed to reconnect it afterwards. A lot of modern cars have airbags in the actual seat (the side airbag usually) and the wiring often runs under the seat.

The best move would be to remove the seats again and check for loose wiring or wiring or connectors that have been damaged of misplaced in the process of the interior’s removal. But before you touch anything under there, disconnect the car’s battery. That ensures you won’t have an accidental airbag deployment that could injure you while you’re working in that space.

This sounds awfully like badly worn transmission. The Dualis in automatic form used what’s called a CVT. Instead of gears inside the transmission, the CVT has pulleys and metal belts that vary their relationship and, therefore, create the various 'gear ratios' the car needs.

When these pulleys and belts wear, they can start to make the noise you’re reporting. And, just like your car, it will get noisier as time passes. Unfortunately, you’re probably looking at a transmission overhaul or rebuild. If you continue to drive it as it is, you’ll almost certainly do more damage, although it sounds like the real damage is already done.

Take the car to a transmission specialist who will be able to accurately diagnose the noise and take it from there.