calsworld - I wouldn't worry too much, as the chances are you did conceive later on, rather than doing anything to damage the baby's growth.
Two things that make a difference - one is that even if you have a 28 day cycle, you don't necessarily ov on day 14. People vary a lot with this, and you can't tell.
The other is that messing up your routine can delay ovulation - and a holiday is a classic way to do that. So you could have conceived a few days after your holiday ended, even.
I started to find out about this because was having problems conceiving, and got into temperature charting to find out when I was ov'ing (your temp goes up when you do). I wouldn't be pregnant now if I hadn't, as that cycle I ovulated almost a week late, did the relevant deed, and hey presto!
If you're worried, do go and see your midwife, but I bet you anything that you weren't ovulating when you thought you were.
And poor you with the bust of pain - mine's sensitive, but nothing like that. Perhaps start a thread on the pregnancy page and see if anyone has some advice...