How can I differentiate between a temporary ADHD hyperfixation or a true passion for something?

I've been having somewhat of a new ADHD problem, and not sure how to overcome it. I always get into a new hobby or work interest that I become really fixated on and most of the time I completely lose interest after a while.

My new problem is knowing that my new interest could just be a temporary hyper fixation, I end up not doing it at all and have kind of just been stuck not doing anything because I don't want to waste money or time on something I'm going to lose interest in.