While much of that article is useful, it is not advisable to give human medication to any animal without veterinary advice. Many can have very serious side effects. If isolating her is possible so she gets a chance to rest it, then do so for a few days. It may be worth a trip to the vet for some chicken friendly painkiller if she is limping badly.
Egg bound chickens will tend to look more like a waddle, and you can often feel a firm, egg shaped swelling underneath, behind the ribcage. If you have her isolated to rest her legs/feet, you will see if she is managing to lay.
As it says in the article, warm baths can help, but putting a finger up the bum usually won't! Pressure over the egg swelling towards the bum might, but they can need injected with calcium, pain relief, or even anaesthetised if it won't pass.
Most likely would be a knock or foot/leg pain, so rest plus or minus pain relief - you should be able to give an educated guess as to whether she's sore /lame enough to need this, and if not better in a few days or off her food, she will need the vet.