experiencing a sharp pain after having a dental crown done

If you returned home and you have sharp pain when you eat or when you wake up in the morning and other times it's fine, this is not usually anything to do with infection.
The most common case here is that the crown that we've done is slightly too high and what you need to do here is visit a local dentist or you can check it by simply bite on a piece of paper to see the impression of the teeth. If you feel this kind of pain, it needs to be done quickly because if you leave it for a few weeks it can aggregate the nerve under the tooth and you may have further problems with that.