Kate, I already take Cymbalta for depression...I also know how I feel-felt about my father. He is deceased and I still have ongoing issues about my youth and adulthood. I mostly need to know what I can do to be able to help my son if I am here alone with him or myself because my heart races to the point I feel like I am dying and I also have tachycardia which makes it worse...
It may also help you to use imagery to help you see yourself helping your son. Start by imaging your son telling you that he feels sick. Then sit with that thought until you feel calmer. Then go to the next step and imagine your son saying he might vomit. Sit with that until you feel better. Keep going until you are able to think of these steps without feeling overwhelming fear. This would be easier to work on with a therapist but you can also do it alone if needed.
It also helps to learn how to relax. Here is a resource to help you:
The more you practice this technique, the easier it will be to stay calm when you feel anxious.