How to tell if i have autism and never been diagnosed?

Yes, but: Autism is much more commonly diagnosed now. Some think it's diagnosed too often. As a 49 year old, you went to school at a time when mild autistic disorders were overlooked. Those kids were just seen as very shy or very eccentric and typically shunned by peers. As adults, they are now often seen as suffering from aspergers. Counseling can help but you need a therapist who isn't afraid of bluntness.