Of course. Flashbacks can be symptoms of other disorders eg. Acute Stress Disorder. Also, many people fit some but not the complete criteria for PTSD and may fall into a generalised anxiety disorder. For example, I know a woman who recently lost an infant to SIDS. In less than a year she has given birth to another infant, same sex, same prematurity. She expressed lots of triggering reminders that are causing her nightmares and emotional overwhelm. However, she does not identify with other PTSD symptoms in what she is expressing. You could call it a grieving process. Like the written piece here on resilience and how some people avoid development of PTSD, it can vary how individuals respond to trauma and what coping resources they have in place.
