A GP visit is definitely in order, as it could be lack of iron or vitamin B12, or perhaps a thyroid problem. None of them the cause of my awful fine, thin hair, which is genetic, but you need to rule out medical causes first.
I must have spent a small fortune on various pills, potions, specialist extensions, creams and powders over the years.
Currently I use Batiste dry shampoo (lots of Batiste), buying in bulk when it's on half price offer, Fibrology shampoo, Viviscal supplements or similar, and the occasional false hair messy bun, which cost a fiver or so and pin on with a couple of hair clips. I hope I never have to go down the wig route, as I imagine they're uncomfortable - has anyone experience of this?