So me and my partner did the 'deed' on November 1st, it is now November 23rd. My period is due today, I woke up with very very slight dull cramps and thought well this is the start of it but when I went to the loo, it was just very light pale pink, as the day has gone on, it's just very pale spotting. i have never in my life had spotting. my usual periods (even from day one) is usually very very heavy clots and severe cramps to the point I'm usually almost throwing up from the pain. I've never had a period that's just spotting and dull cramps.. so I guess my question is, is it possible that it's implantation bleeding/cramps? I did test a week ago but it was negative, which I kind of expected anyway so decided I'd wait until a missed period before testing again. Is it even possible to have implantation bleeding 3 weeks after possible conception? i always thought it was within the first week to 2 2 weeks?

Women ovulate two weeks before their period, not three. No matter how long your cycles are this doesn't change by more than a couple of days from woman to woman. Did you only have sex on the 1St, no other days afterwards?

I understand that but I also read that sperm can live in your body for up to 7 days which makes it still sometimes possible to get pregnant? Yes was only the 1st as I've been feeling rather poorly since then and haven't wanted to do anything 

Sperm can live for up to 7 days but the general rule is 3-5 days really. The egg only lives for 24 hours after it's released so depending on when you ovulate (can you confirm OV day?) will depend on whether there is a possibility. The only thing to do is wait 4 days and then test again as if it is implantation it takes 4 days for hcg to be detectable on a test. 

I don't have a clue when I ovulate, I've never checked and I used to have really irregular periods, theyre still sometimes irregular now. Just wanted to say, the spotting has stopped and its now just light brownish stuff which I assume is old blood? ive never in my life had a period like this. usually they are always extremely heavy from start to finish. I've got the dull cramps and dull back ache but nothing like a normal period. i keep wearing panty liners just incase anything comes out but it doesn't, it's only when I wipe and there's not much of it at all 

That's what my period has been like sinve ny MC think my hormones are getting back to normal.... this month i have had the proper CM and I temp to confirm ovulation. If you are unsure of your cycles then it might be better to track for a couple of months so you are aware of the signs. Ovulation is generally 2 weeks before a period is due but if your cycles are irregular it will be difficult to say for sure 

So I tried working it out on an ovulation calculator. we did the deed on the 1st & it says I would have ovulated on the 6th. so that's 5 days after the deed? so if sperm can live up to 7 days maximum, could it still be possible that this is implantation? I'm just a bit confused as I've never in my life had a period like this. Every single period is heavy from day 1 to the end and I'm usually in agony. This is the first time in my life I've had spotting then this brown stuff when I wipe which I've read is old blood?

Those apps aren't reliable at all especially as you have irregular cycles because they just guesstimate a day. My app, despite me having approx 26 day cycles has me down as ovulating this weekend because I had one late ovulation on day17.... I actually ovulated Tuesday. If I had listened to the app I would have missed the window completely!

it could be possible.... bodies are weird. All you can do is take a test but it does seem unlikely. Implantation is meant to be between 6-12 dpo But can sometimes be later. 

i would take a test to rule it out but rule of thumb on the PG tests is to test 19 days after sex.... you are well passed that now. 

Maybe next time use ovulation sticks or temping or both, especially as you are irregular... takes the guess work out of it 

Also my last period was just pink and brown and just when I wiped... didn't need any sanitaryware.... doctor just said was a hormonal blip.