How do I figure out my cycle

[YourNewspaperIsShit]

So I'm a tad confused about the whole CD thing. I know I get AF on the 21st of every month and it's v heavy (like super plus plus) but only lasts about 4 days (sorry if TMI)

My CM makes it really obvious when I'm ovulating and the past few months it's been about the 11th, but online calculators say it's should be the 2nd-7th unless I'm using them wrong

Someone help me figure all this out please

Your online calculator sounds a bit odd!! I use Glow and log my period and the app does the rest! I use opk and log the results etc.

What calculator are you using and what fertility signs are you tracking?

Fertility Friend has a series of free tutorials on their site/app which I found useful for understanding how tracking works and how cycles can vary between women. Even if you just read through the first few and skip the later ones. I feel like I understand my cycle very well now based on that information.

Thanks I'll download that now I just used one off Google but i think I've put the wrong amount of cycle days in coz I don't actually know what they are so I said 30 because AF arrives the same day every month

It sounds like the calculators are probably just using counting and assuming a typical luteal phase of 14 days. Remember the fertile window is the 5 days before ovulation rather than any time surrounding it. So the app is literally just counting backwards from 21st and getting 7th as an ovulation date.

If you input your CM and any other signs you're tracking - temperature being the easiest for a website to interpret, OPKs providing useful information as well, it should get a clearer picture. If you think you're regularly ovulating on the 11th that would give you a 10 day luteal phase which is still within normal but is just borderline for being too short. It would be worth tracking this for 3-4 months more in detail so you can be sure and then if it is 10 days or less, taking this information to your doctor as there are medications they can give you to lengthen the luteal phase.

You can google luteal phase if you've no idea what I'm on about - I need to rush out! But it should give you a starting point, anyway.