Usually the only emotions that I can physically feel are the negative ones. My most recent experience was at the funeral of one of my best friend's dad. I've known the family for years, but everything didn't really hit me until the funeral service. Seeing my friend and his family standing at the front of the church next to the casket was overwhelming. Sure, I've been feeling my own emotions through this whole experience and it's been draining, but the feelings of loss and anger felt through empathy were the most intense I've ever had. I couldn't stop shaking, my muscles were clenched, and I couldn't stop myself. Everything came over me in a flood, and I was no longer in control of my body.
When my nerves are shot (like they are right now) anxiety and stress manifest themselves through an unsteady heart beat, and obnoxiously shaky hands.