There are a large number of reasons why you might have hip pain, but the most obvious/common is arthritis of the hip joint. This affects many otherwise healthy people over 50, and is likely to be worse in PPS patients due to the abuse the hips have gotten over the years.
I'd strongly advise you to discuss this with your doc and set up an appointment with an ortho doc of some flavor. (Whether to start out right away with a surgeon is always a touchy question.) But you may well be a good candidate for hip replacement surgery.
Another possible cause of the pain is muscle injury. This is sometime triggered by statin use in PPSers, and sometimes occurs even without statins. But this pain won't feel like it's IN the joint, but rather you'd have a sore butt or stabbing pain running down the leg or some such. This, of course, should also be discussed with your doc.
Then the first thing to do is to stop doing what you're doing. Even though I'm an advocate of exercise for PPSers, when you have your sort of pain it means that damage is being done and it's important to quit doing more damage. This is not something you can just "work through".
Two main possibilities as to the cause:
I happen to be quite sensitive to statins, and, in addition, I probably have myoadenylate deaminase deficiency (MADD), a genetic disorder that makes one more susceptible to metabolic injury. There are several other genetic disorders (McArdle's, CPT II deficiency, mitochondrial diseases, et al) that can contribute to this problem.
You need to figure out what specifically is causing your problems. If you are taking a statin (Lipitor, Crestor, Zocor, et al) I'd strongly advise you to discuss temporarily stopping it with your doc. (And don't take no for an answer.) If statins are a part of your problem you should feel significant improvement within a week of stopping the drug.
If you want to see if you have MADD, the simplest way to diagnose it is to get hold of some D-Ribose capsules (mail order or perhaps at a store that sells supplements to weightlifters, etc) and take about 15 capsules a day for 3-4 days to see if the pain is reduced. (In my case the pain reduction was dramatic, and within two hours.)
But even if you get the main part of the pain to stop, you will notice that there are still painful spots in your muscles. For muscle/tendon strains these take about 6 weeks to heal. For metabolic injury it takes about 6 months. You must avoid reinjuring the muscles before they are entirely healed -- you can begin to exercise after a few weeks of clearing up the cause of your pain, but you need to avoid anything that provokes a "shooting pain" sensation.
Actually, there is another possibility, and probably less serious: Piraformis syndrome, sometimes called "false sciatica". This is caused by nerve entrapment in the buttocks area, and is apparently more common in those with poorly developed gluteal muscles, and in those who sit a lot. One simple (but unreliable) "diagnostic" is to see if the pain is partially relieved by walking with the toes pointing outward.
If this is what you have, simple physical therapy (properly directed) can usually provide substantial relief within days.