no period but also no sex??

[needtoknow]

My ex and I split in June so I haven't had sex since then. I had a period in June, July and August but skipped period in September and am due to start now but have not yet. I have been on the pill for 15 years, haven't taken any antibiotics and haven't made any changes to my diet. I started a new job in August so I knwo I have been under new stress. I have gained some weight in the past 6 months but not a huge amount. I have had an enlarged thyroid for years but every time they do blood work it comes back normal and I went to an endocronologist a few years back and he said he didn't think it was enlarged enough for him to be concerned. I have had my throid ultrasounded and they can see that it is enlarged but they don't see a mass or anything. What could be causing my missed periods?

[moonisis]

I missed a period once due to heavy stress. Also changes in weight can throw things off. Also my period was wacky when I didn't get enough sleep, didn't eat enough and didn't mentally take care of myself. If you're going through a rough time at the moment, perhaps your period could be on vacation from stress.