Polbilly is absolutely right...
It takes a while to get pregnant... when you think about it, you release your egg once a month (ideally) and for the time it is released it is available to be fertalised for 12 hours (approx). The idea is to try and pinpoint when you are
ABOUT TO ovulate (release your egg) and start BD'ing then, perhaps BD'ing every day or every second day around that time. The perfect situation is when your DH 'boys' are waiting for the egg to be released, but sperm can stick around in your body for serveral days (provided the environment is right).
If you think you can get pregnant straight away, I think you may just be setting yourself up for disappointment. My DH and I tried for 14 months, it became a bit of a science trying to get the timing right with basal body temps and ovulation sticks but it was worth it.
Give yourself a break and relax about the time frame issue. Get to know your body's rhythm and come up with a plan on what indicators you will use to identify your fertile stage.
Good luck....