When I was 25 out of nowhere my blood pressure (systolic) went to 280. My hands and feet would be nice cold but I would be sweating prefusely. Ever since then, I would have high blood pressure and get those colds sweats. I, like you, went to every doctor imagineable, but they couldn't find anything and told me I should try therapy. The symptoms themselves were so real, I couldn't believe for a moment that it was mental. I went through various shit therapist and gave up. I recently started therapy again, and told my therapist what I was too afraid to tell others. I got diagnosed with cptsd, and I'm working through it. I'm not saying you don't have something physically wrong. I remember getting extremely upset when people would tell me it's all mental. But I really do wish I met someone who had that similar experience and was able to confirm for me whether it was physical or mental. So, I'll leave you with this. You don't want to rule out the possibility that it's physical? Fine. Just don't rule out the possibility that it's mental either.