As they grow older, the frequency of sheds decreases (This applies to most snakes and lizards). If you feed less or it is underfed for babies, the shedding happens less frequently. So I would weigh her in grams. There us a feeding chart in the husbandry section. Your snake may be needing a large mouse at thus point but it is hard to tell without a weight in or pictures for comparison.

One thing you don't want to do is panic and do more than you have to, thus stressing out your snake. A maintained 50-60% humidity is good. When she goes into shed, bump it up to 70-80% humidity. Signs of a shed are covered eyes ("going into blue"), dull looking scales or have a light shade of coloring than normal, pink bellies, reluctant to feed, may soak a lot or stay on a hot or cool side more than usual (Not as active at night).

Don't worry though. I have herp babies that shed every 2-3 weeks to adults that shed like 3x a year. They know when they are. Stuck shed happens AFTER a shed had started, not before.