Hair loss is actually reasonably common after weight loss surgery, believed to be related to fewer calories taken in and calories being directed toward the organ systems that need them. Hair unfortunately loses out. The exact cause is not entirely understood, and so the treatment is a bit more difficult to determine. Most doctors agree that it tends to be temporary and improves once the body re-equilibrates after the initial period of significant weight loss has ended. It's important to talk to your doctor about appropriate vitamins and other supplements that you should be taking. Take care.
I don't know. I experience some hair loss when I'm severely stressed.
There is also a hair loss/ alopecia community which may be able to offer support/ advice.
At least in the interim till you get feedback from the doctor.
J