Episode Two - S2-E2
Continuity mistake: Nessa goes home to Pam's house along with Stacey and Gwen, and in that scene you can see the tattoo on her arm of the Welsh dragon. If you focus enough you can see the dragon only has 3 legs, whereas the Welsh dragon has 4 legs, as does her tattoo usually. Both writer Ruth Jones and director Christine Gernon confirmed this on an outtakes special.
Episode Two - S2-E2
Revealing mistake: When Pam opens the door to Gavin Mick Bryn and smithy after smithy went to the driving range you can see 2 Welsh dragons on the mural behind Pam. Even though Pam and Mick's house is filmed in Wales they live in Essex in the show, in England.