Amenorrhea?

Sara🌸
This is my first eve post, so we'll see how this goes! 😅
I turned 21 this Fall, and I had my first period when I was 9.  Since then I have always had irregular periods, and recently have been becoming more and more sparse. 
Over this last year I have experienced more abnormal cycles--or lack of them.  I just got my period a few days ago after not having it for 4/5 months!  This has happened a few times before, but with only 2-3 month gaps. 
I have to find a new doctor to schedule an appointment to see what is wrong, but I looked up symptoms and amenhorrhea seems like a plausible condition.  
Has anyone else experienced this, or suffer from the same thing?  It is extremely stressful and frustrating! 😓
Side note: I was on the pill for about 8 months and they made my cycles regular, but at the cost of extreme moodswings and depression so I stopped taking them about a year ago.