If you are only using a heat lamp and have no covering on the tank, chances are you are going to be dealing with a very bad shed.

You really need to either get a smaller tank for the little dude, or get some sort of top for the tank. A piece of plexi-glass with holes drilled for ventilation would work.

Also, only use lamp heat as a supplement. Belly heat should be your primary source of heat. You should be measuring your hot side temperature with a digital thermometer with a probe. If you are using anything else you are not getting an accurate reading.

You also need something digital to read humidity. Your snake will need between 60-70% humidity during the shed cycle.

Honestly, the cheapest and easiest option would be to put the snake in a tub until it is older.