Stress and anxiety can do a lot to the body. When I have large amounts of it I feel nauseous and get muscle aches exp in my back. You mention you are in great shape so working out is a great way to reduce stress/anxiety.
Hey there:)
Take a deep breath, everything is okay. I know that's what everyone says, but I understand. I have these problems too. For a year now I've been having severe anxiety issues. I too get chest and arm pain. There's nothing seriously wrong with you, you're gonna be fine. To answer your question, stress and anxiety can cause these symptoms. Here, I'll share a link that might make you feel better. It makes me feel better too. It's just a list of anxiety symptoms: http://www.anxietycentre.com/anxiety-symptoms.shtml
I used to have upper-abdominal pain that would go away whenever I didn't think about it. Trust me, you're okay. It's just stress that's making you think you have an illness, or that there's something wrong. I've been there. If you need to talk, just message me and I'll get back to you:) we can get through it together! Hope I helped!