Are you saying that you're having problems while running calls or is it only the fallout afterward?
I too ran into problems going through medic school. Lovely mix of getting in over my head by going straight to medic, taking on too much outside of school, preexisting depression, tragedy earlier in the year, and running into unexpected triggers.
At this time, I'm gaining experience at a Basic level service before taking another run at primarily medic level work, my money-making job is very low-stress (and low pay ;P ), and no one in my circles has died recently. It can get better, but you have to be willing to possibly make major adjustments. Maybe consider taking a step back from medic, or altering things in your life outside of EMS. As regards specific episodes of anxiety, have you noticed anything in particular that makes It worse? I find that specific situations and people make it harder for me to function optimally. I can still function OK, leave those pitchforks where they are, please. It's just not fun to have to work through that.
Even with specific triggers, some are manageable. I had to work with a guy pretty regularly for some time, and I started dreading it, because when he became upset, he had mannerisms that my brain was trained to interpret as warning signs. Not actually any threat, but it's harder to enjoy the shift while epinephrine is pounding every receptor that it can find in your body. I eventually talked to him about it, which didn't go so well. Tried again, something clicked, and we had a great conversation. Some triggers aren't manageable, though.
I'm not going to tell you to get out of EMS, I'm not going to tell you to stay. It'll be hard going either way. Do consider, though, what do you love about EMS? The amazing elements of this job are conveniently packaged in the ambulance, but can also be found in associated fields. Think about your values and goals, look at all your options, talk to more experienced providers and trusted friends, and make an informed decision. I wish you the best!