Exercises I can do without being on my feet without weights?

I started my diet last week and along with it came exercising. However I think I was overdoing it and I hurt my foot in the process. I tried to walk today but it was very slow going so I felt it wasn't worth potentially making it worse. I want to keep working out though, do any of you know of any exercises I can do while sitting down without weights? If I had weights I could probably come up with something but i've been doing all of this at home.