22yr female. Experience the following symptoms: angioedema, chronic urticaria, anaphylaxis, bone/muscle pain etc, is this systemic mastocytosis?

Serum tryptase level. You're certainly describing an entity that sounds histamine mediated but of course can be due to other causes and mediators. Does she have urticaria pigmentosa? Have you done a serum tryptase level? To my knowledge the one definitive diagnostic is a bone marrow bx. The other lab i look at to asses a histamine mediated process is anti high affinityfc epsilon receptor antibodies. Any meds?
Not sure. Symptoms like you describe can be found in serious rheumatologic conditions, require laboratory testing and biopsy, and serious medical consideration. Get moving on seeking expert medical opinion now. If you have had major weight loss, or weakness (difficulty walking) do not accept delay in the appointment.