Is there a way for me to make a complaint against the suicide hotline

Do you call a lot? Suicide hotlines have to triage and are often short staffed.

Were you listening to what they were saying or were you too distraught?

I've had this happen and in hindsight realized that someone else was a much higher priority. While it sucks, it has to happen in certain circumstances. Maybe they had someone on hold in more dire need.