I had a fall on my mountain bike recently and landed on my hip. the region is now still swollen and is quite hard. is this cause for concern?

Likely hematoma : It is likely a hematoma, which is a area of bleeding that can occur secondary to Injury and other causes, when it forms a clit it hardens. I do think it would be good to be seen to verify the diagnosis and to rule out an associated fracture.

Trochanteric: Bursitis . I believe a steroid shot would improve you greatly! I am a heavy duty mountain biker. It happens frequently with your fall!

Hematoma: With the trauma as described would be concerned about a possible hematoma you should seek an evaluation