What Causes Pain In Groin And Hip Area?

I've had an ache in my left groin/hip area now for about 3 months. I can now not sit cross legged without it hurting and it's hard to get into certain positions. I've now just started to get pins and kneedles in my foot which runs up my leg when I walk on it. At first I thought it was just from the new bed I was sleeping in, but it's now still there and I'm worried it might be something serious.