weird period on Nuvaring

I'm in nuvaring. I was on nuvaring when I was in high school to regulate my periods but stopped. When I came to college I met my boyfriend and started it back up. I recently had my period and it was extremely light and short, which I haven't experienced before, even when I used it in high school. We have had a conversation break while I have been on nuvaring. I'm worried I could be pregnant and just having light periods because of the change in hormones when I'm taking the nuvaring out and putting it back in. Has anybody else been on nuvaring and experienced this? Or should I be running out to take a pregnancy test?