Gulp. DH has been overseas and we got a little carried away on his return. We usually use condoms.
I thought it would be ok as I was on CD5 and still bleeding a bit. I've just double checked and the conception calendar said that this was the first day of the most fertile part of my cycle as AF has been 23 days apart lately. Cripes 
Now, our first child took 4 months to conceive. This is really unlikely isn't it? AF has been between 21-28 days since I wound down breastfeeding. What do you reckon?