I am a 20 year old female using the Nuvaring birth control. My period is 3 days late, with only very few, and tiny spotting. I took a home pregnancy test yesterday morning and it came back negative. I am having a lot of symptoms, including lower abdominal cramps, constipation, slight nausea, food cravings, and I am very sensitive to food I normally love. I am fatigued a lot during the day and also having some lower back discomfort. I just recently had thyroid surgery, (whole thyroid removed) so I don t know if these symptoms could be from that, or what is going on. I had a miscarriage in September, so I am pretty nervous about this! Help?