My last period was October 11th. I had unprotected sex on the 23rd and I ovulate today the 25th. Could I be pregnant?

Yes, you could get pregnant.

I would know for sure if I am when I miss my period or is there a way of knowing before that?

No, there isn't an accurate way to test before that.

So since I had sex on the 23rd and ovulated on the 25th does that mean if I am pregnant it conceived on the 23rd?

Sperm can live inside of your body for several days if the conditions within your body are right for it. So there's no way to determine the exact day of conception, if you are actually pregnant.

You cannot get pregnant before you ovulate. I don't know why you are sure that you ovulated on the 25th byt pregnancy cannot occur unless there is an egg to fertilize.

I know my body and I keep track of when I ovulate. There is such thing as sperm staying in a woman for at least 5 days than obviously if you ovulate and sperm is still in there than you can get pregnant.

Again, if you are sure you ovulated on the 25th, then you could not be pregnant before then. If there was no egg to fertilize on the 23rd, pregnancy could not have occurred. If sperm was present in your body when you ovulated, then YES, AGAIN, you could be get pregnant after you ovulate. Again, there is no way to tell if you are pregnant other then testing, preferably a week or more after a missed period. Did you have any other questions we can help with?

Thanks for your help!