hair :(

Do you straighten/blow dry your hair?

I would think that the reason your hair is dry is because of that? Do you put anything on it before drying it/straightening it?

Heat protection spray

Hmmm, can't understand why its dry and frizzy then. Try letting it dry naturally or not straightening it once a week. Perhaps try changing your shampoo if your hair is getting greasy frequently, that usually does the trick for me. You could also try using a shampoo for dry hair, boots do a coconut one

short hair does tend to get greasier quicker, well, probably it's just that you don't notice it with long hair. You'll probably just have to wash it every day.
Did you have it dyed at the same time as you had it cut? Some dyes can ruin hair...
if not .... hmm... maybe try some moistourising shampoo and conditonier

do you know a decent Shampoo? At the moment, I used a ‘sleek and shine’ one.

I use Tigi's Fashionista Shampoo safe for coloured hair, or something like that, its purple anyway. I don't have coloured hair, but my hairdresser recommended it because i straighten/blow dry my hair nearly everyday and aparently colouring does similar damage. I also condition it once a week using the same conditioner. Its quite expensive but it lasts quite a long time if no one else in your house uses it! And it smells nice, of berrys!

thanks