You might be entitled to a written summary of your therapist's findings, including her suspicion that you might have a pervasive developmental delay. You should find out if you are entitled to such, and in the event that you are, obtain the written summary.
You should present this information (ideally in a written summary from the therapist concerned, but alternatively convey the information verbally) to your current therapist, indicate why you think it needs to be pursued, and request the current therapist refer you, for assessment, to someone suitably qualified in the diagnosis of autistic spectrum disorders in adults.
If there is a finding (subsequent to assessment) of an autistic spectrum disorder, you should probably inform practitioners involved in the assessment of your (biological) children of the finding.