Hi Angie,
Is either your GP or the specialist that cancelled on you able to tell you exactly what the "vascular" issue is called so that you can do some research and better understand what they are saying is the problem while you wait to see the foot doc and podiatrist?
I, too, have had problems (knee and back) since my THR surgery and had not been prepped for this possibility ahead of time and not had much information proffered from the OS about the problems afterwards either. My OS also focuses on the hip and the implant -- it's just where their focus is, by design of their specialization. For people like you, me and Ann -- and hundreds of congenital hippies before & along with us, the Perthes or Dysplasia condition that we were born with and lived half our lives with makes the THR surgery a bit more complex to recover from and adjust to. We have soft tissues (tendons, ligaments and muscles) that have a tremendous adaptation that must occur after we get the new hip. The alignment of our entire side is changed -- completely, and even thought it may be only by inches or centimeters that is enough to cause pain and disruption in various places. Our other joints are trying to compensate and adapt -- our low back joints, knee joints, ankle joints, feet are all adjusting to these tiny changes that have come about with the new hip.
The OS doesn't talk much about this to us ahead of time, maybe it's because he cannot predict who will have a difficult time with this adjustment and who will not -- he just doesn't know. It is frustrating, but one of the things that I try to console myself with is that when I see the OS he says the appliance is fine -- everything is healing nicely and in it's proper place. Next, over time, I've had to try to find other professionals that can help me with the soft tissue adaptation. These may be professionals like physiotherapists, massage therapists and acupuncturists. Of course, as you mention, having access to similar stories here on the forum is helpful in allowing you to see that you are not the only one with these post-surgical experiences.
I don't know if any of this helps you at all and I hope you don't have a horrible day because of those docs. You are only 4 months out from a surgery that has changed and impacted your entire body and now you need to try to give yourself plenty more time for healing and adapting to occur. Hopefully during this time you'll get further reassurance from some medical & para-professionals in dealing with your knee and ankle as well.
Take care,

Cardie