No period 4 months. ADVICE PLS

I came off my pill after my last period in the last week of May 2017. It's now exactly 4 months since that last period and I'm a little worried?! I know I'm not pregnant I've done numerous tests. I wanted to find out peoples thoughts/similar experiences because I know that sometimes it can take between 3-5 months for the period to come back. I'm just worried as I do have a cyst on my pituitary gland and I'm wondering if the two are connected, because when I previously had the cyst looked at, my doctor said it could cause fertility issues - the only way I'd find out is if I came off my pill and the periods go back to normal - which they haven't!

Advice needed girlssss ♥️