I Don't think it is a mammoth tooth because the fossils in Wigan are 300 million years old and not 10000 years old. I think it could be a piece of calamites fossil. Also, it doesn't look quite like a mammoth tooth.
I have been looking at it a bit more and it looks fully fossilized to me, which mammoth teeth are not. I live in Ossett West Yorkshire. UK and I find loads of calamites. I suggest you keep looking because if you look quite often you'll find something bigger. I have found a fossilized tree trunk which is 5 m long, but it was too big to take out of the ground, and a few smaller fossil tree trunks. If you go to discusions, go down to the question "is this a calamites" and you will see a calamites fossil which I found.