I would suggest you see your GP first, hopefully he will send you for an x ray. If your hip is seriously worn (mine was at 70), you can see as many physios and do as many stretches as you like but it won't do any - don't ask how I know. Cycling itself is not usually damaging to hips so if you don't have stiffness, getting up and down from your chair or getting in and out of a car or doing long walks for example, it may be something else. In that case suggestions above regarding physio will be very appropriate. I just wasted about 8 months with physios before visiting my GP and would have been sorted that much sooner had I done that first. Incidentally I was back doing my normal distances on the bike within 8 months - although it took a further 8 months before the new hip was fully up to speed. Good luck