I have another update. Buttercup is still recieving metacam three times a day, and bactrim twice a day. I think that when I took her to the vet the first time she had the beginnings of an URI, as the day after I noticed she had a mild clear discharge. However the antibiotics have since helped that.
As for her foot, it remains swollen particularly in her toe and the area just below her nail. Overall the swelling has come down, as you can see in this collage - the left picture being the picture I took yesterday
I have an appointment for this Thursday which I think I will keep, even though the swelling has come down somewhat. I think it is not bumble foot, but a broken toe, although her toe is crusty which is a symptom of bumble foot.