Tesco pharmacy is at the back of the store next to the medicines aisle (finally they do something that makes sense) and i've always found it to be extremely helpful.
They are open later than any other pharmacy that i know of in the area and from what i've experienced, they will always help you. They do tend you try and palm you off with the tesco products rather than brand but i've also found these to be just as good, just a quarter of the price.
Definatley worth a visit, good opening hours, friendly staff 9 out of 10 read more