WoW, trazadone is a pretty heavy anti-physc med. I've had it and also had a bad reaction while using. Please be very careful with this med on your tiny baby. I'm fearful for you.
I would think that xanax would be a better med for your pup. I take xanax the night before if I know that I'm going to have a stressful day and I wake up calmer and stay that way into the late afternoon when it starts to wear off. I only use .25mg. and I'm a 130 lb woman.
Have you tried trazadone before on you pup? This is scary. I'm sorry if I'm projecting my own anxiety on this situation so please forgive me.
Good luck with the dose.