Yes, breathe, and use your idea, to take your meds. Are you safe? If you are, verbally remind yourself you are safe. Notice the space your are in, are the doors locked? Verbally invite yourself, each part of your body, to relax.
Can you do something to help you feel sensations that you like, like a heating pad, a bath, gently stroking your arms? Wrapping a sheet or blanket around you?
Playing music that soothes you, or (exploring the expressive way to work through a trigger--moving to the music, and using your voice; imagine/verbally say what boundaries you want, and move your body to set the boundary. (Maybe say, "get back". Then verbally support yourself, " I am good to set boundaries."
One thing I do when triggered is to slowly talk out loud, verbally engaging, and describing what I am doing when I move around to do daily tasks. It helps me associate.
I will ask myself, many times, and slowly follow what comes to mind, "What do I need?"
It is helpful for me to remind myself that the trigger cycle takes a while to wear off. The frozen part is normal and it will wind down in a few hours.