Never had it in my life but last few months have been experiencing unexplained severe anxiety. stretch marks also appearing on arm. what is happening?

See your doc: There are lot of possibilities what could be happening, but first, don"t freak out because you're not gonna die from any, ok? Big deep breaths.. In through nose.. Out through mouth.. Nice, slow.. Relaxed? Ok. You need bloodwork done, b/c aside from most common cause (stress and wt gain) you could have a few things, all treatable. See your doc, tell your story. If you use steroids, that's the prob.