Could very likely be the risperidone. I don't know how long you've been on it, relative to your period stopping, but it really messed up my cycle from the very first time I started taking it. I'd only get random periods every 3-6 months, but they'd be super heavy and last for about 10 days, and then they just kept getting longer and longer in between and shorter until I hit menopause.
But it's probably worth checking with a Dr.
splitimage
__________________
"I danced in the morning when the world was begun. I danced in the moon and the stars and the sun". From my favourite hymn.
"If you see the wonder in a fairy tale, you can take the future even if you fail." Abba
