I had a bad dream and I dont want to backslide... is this normal?

Hi, I want to start by saying I'll definitely discuss this with my therapist when I can next see her, but in the meantime I wanted to maybe hear from others going through similar things.

I was diagnosed with chronic ptsd due to a year-long series of roommate-related ordeals that lasted roughly the entirety of 2024. I couldn't start emdr therapy until roughly April and I did about 3 sessions total. After my third session (lets say it was about the beginning of May) where we closed up some unfinished processing, I spent time at my mom's place for a week and saw immense improvement in my mood/symptoms for the next few weeks.

Here's what scares me: Last night i took melatonin and had a bad anger-filled dream where I was stuck with the few people that contributed to my trauma in a car and I basically just flipped them off in my dream and it was filled with anger.

Does this mean I'm not "healed"? Is the occasional bad dream (esp on melatonin) normal this long after feeling improvement? Am I not done processing?? Is this nothing to worry about??? I've taken melatonin as necessary over the years and it didn't cause nightmares at all until my trauma, just more vivid dreams.

Sorry this is a mess, I've just been scared to feel the symptoms again because of how debilitating it was for the past year. Thank you if anyone reads this.