For the first few days after the trauma I was far too sick to exercise. My nervous system was completely shot and I just needed to rest and calm my mind and body. I went back into the gym about a week later and suffered pretty severe anxiety during my workout. I was anxious about having a panic attack in the gym and it wasn't so much that I didn't want to have an attack inside a gym, it was merely the fear of the panic attack itself. That night I had attacks and I think it was because my body wasn't ready for the nervous system stimulation that follows a heavy weight training session. First mistake - going too hard and heavy like I was used to doing.
About another week later I started working out at home. I was lucky enough to have a basement gym with plenty of equipment to get a good workout in. I also had a stepper machine which I started using almost every morning as well. Remember, there are two parts to working out. Cardio and Weight Training. Both are important and both should be incorporated into your recovery.
When you perform cardio your body actually burns up that excess adrenaline rather than having it circulate through your body all day. Lets remember adrenaline's prime function is the 'flight or fight' response so give your body what it wants and RUN! Or walk, step, swim etc. It doesn't really matter, just get your blood pumping. Not only does it use up that adrenaline but it produces serotonin, the mood enhancer, which most anti-anxiety drugs are made with. What!? So you're saying that instead of taking a potentially harmful drug I can just go for a jog for free with no risk? YES!! Cardio can also increase the activity of the neurotransmitter, GABA, which inhibits brain activity or 'quiets' the brain. If you have anxiety, you know that 'shushing' the brain to us is like what candy is to a kid.
Study after study after study has shown that exercise decreases the symptoms of stress, anxiety, and depression. Just google it! If you aren't exercising yet, then do your brain and body the biggest favor of their lives. Give yourself some peace and relief. Burn up that excess adrenaline. Release some 'feel good' hormones.
Keep your rep ranges higher, 20+ reps on each exercise, and don't incorporate intensity techniques like dropsets or pyramids. If you don't know what those are, don't worry, you're probably not doing them then. Sessions should only last 30-45 minutes and no longer. You don't want Cortisol levels to elevate which can exacerbate the problem.
It is still very important to continue weight training because you MUST maintain your muscle for good health. You can actually go into a catabolic state (muscle breakdown) when you have anxiety and if you don't use them, YOU LOSE THEM.
The severity of your anxiety is also going to determine the level of intensity when it comes to weight training. If you just have a little generalized anxiety, then congratulations, you're normal and should be hitting the gym hard. The above recommendations are for severe anxiety and panic attack disorder, which I suffered from so can tell you from experience what worked and what didn't.