Should I test??

So a little background, I went off depo  last august, had no period until March and then had another period a week after that. I was supposed to start another on April 18, it didn't come so took a test the 19th and it was negative, period has never come now. Having severe pain in my lower right side of my back and feel nauseous, should I test or is it just cause the depo is still in my system?