I'm 22 years old and I haven't had a menstrual cycle for a year. This concerns me greatly. What should I do? Does it mean I won't have kids?

Need eval. You absolutely should go to see a gynecologist and discuss this further with the doctor. Some examination, blood works and sonogram would be needed to check the anatomy as well as the physiology of your reproductive organs etc- and go from there. Good luck.
Need evaluation. This could be due to a variety of things such as thyroid or other metabolic disorder, excessive weight gain (obesity) or weight loss (eg, marathon runners), hormones (mirena (levonorgestrel) iud, birth control pills, depoprovera, etc) or other meds you are taking. It could be a potentially harmful situation especially if you are not ovulating and getting excessive estrogen. Need to have this checked out.