If it happened overnight, I would lean towards some type of injury/dislocation, but it could be one of the deformities I mentioned above (Varlgus-varus, Slipped tendon, etc). I realize money is a concern, but these legs problems are often hard to treat at home, and require vet attention. I would take her there if you can.
If she's having a hard time walking, you may consider putting her in a sling. As shown below.
View attachment 2367069
Are you able to manipulate the leg back into its original position, if yes, you may try splinting/bandaging the leg and see if that helps. If it doesn't bend back properly, I would not splint, as it will likely cause a lot of undue pain on her part.
Here is some info on how to deal with splinting legs, and some further details on some of the conditions I mentioned.
https://www.mypetchicken.com/backyard-chickens/chicken-help/All-about-VVD-disease-H268.aspx
http://www.poultryhub.org/health/disease/types-of-disease/leg-and-skeletal-problems/#:~:text=Slipped tendon or Perosis is,in flattened and enlarged hocks.
https://theiwrc.org/wp-content/uploads/2011/05/Duerr_Splinting_Manual_2010.pdf