Little piece of bone/tooth sticking out from above extraction site

I had my back tooth extracted last week. It's getting better everyday since but it's still sore on the side closed to my gum, particularly if I eat. It's not agony or anything... just painful. With my tongue I can feel a thin pointy shard of jagged tooth or bone running along the outside part of my gum. It's above where the tooth was... its running from bottom to top of my gum rather than from left to right. I rang my dentist to ask about it but he's away and the surgery is closed. On the leaflet I got from him last week it says that pieces of bone "working their way out" from the extraction site is normal. It doesn't give a time frame though.

Is this ok to just leave be or should I be concerned about it?