Regular with a random long cycle??

My cycle is usually a regular 30 days. 
Glow and another app I use are typically accurate within a day or so. 
But last year I had a random 60+ day cycle. After spending like $100 on different tests I gave up, and eventually got my period. I thought I may have ovulated super late or had a possible chemical pregnancy. 
But I went right back to being regular so didn't worry about it...Until this cycle.  
I am on day 42.
I had what I thought was EW CM around the time I normally ovulate, but I'm no pro and I could have been mistaken. 
We are not actively TTC so I don't feel like my chances of pregnancy are super high.
But I know there is always room for error. 
I haven't taken a test yet but I will soon. 
I'm wondering how common it is to have a random long cycle once in awhile?
Does this happen to anyone else?