As far as continuing to run her on the barrels, what does your vet say?
If there is any question at all about lameness, I would absolutely take your horse to a specialize equine lameness vet for an eval.
Swelling indicates there is still inflammation going on in her foot. I can see what you are talking about in the last photo you posted (couldn't tell in the other ones). What sort of injury did she have? How long ago?
Conformation-wise, she isn't a "looker" (don't take that in a bad way though). Her shoulder is very steep. Her whole body is under-muscled. Hindquarters should be nice and rounded, instead of "pointy" like hers are (not sure of the proper term there). Neck is short, but back is long (not proportioned evenly). Hard to tell in the picture, but she may be low-heeled in the feet too. Base narrow for sure; I'd expect her to be pigeon-toed but it actually looks like she wears the inside of her hooves faster than the outside, especially that right foot.
But she looks like a sweetheart. She's got a nice kind eye. Personality is very iimportant too! Not just looks.
∞•*˚ Βгįťţαňγ ˚*•∞
It is not enough to know how to ride; one must know how to fall.