I'm sorry to hear that you are having problems.
C-reactive protein and sed rate are non-specific tests for inflammation. When increased, they indicate the presence of significant inflammation within the body, however, they tell the doctor nothing about the cause or location of the inflammation (it could be localized, systemic, or both, and caused by one inflammatory process or multiple, a pathological process such as infection, or a reactive process such as response to injury). Negative tests do not rule out the presence of inflammation, but the inflammation, if present, is usually less severe.
In order to determine if your CRP and sed rate are elevated because of your hip, you doctor will need to do some more investigating. At the very minimum, this would involve a physical examination for signs of overt inflammation in your hip, and likely imaging and additional blood work, if that has not already been done.
Removing fluid from the hip, itself, is fairly simple and would be similar to having a steroid injection done, if you have ever had one done in your hip. However, instead of injecting steroid into the joint through the needle, your doctor would remove fluid from within the joint, instead. Then, depending on how the fluid appears and what he thinks the cause of the increased joint fluid might be (infectious vs purely inflammatory), he may also send a sample of the fluid to the lab for analysis. So basically, you are talking about probably 2 needle sticks -- one to numb the tissues around your hip, followed by the actual needle used to remove the fluid from the joint.
I've had many joints and other body parts injected, but never my hip. Joint injections are generally uncomfortable/not fun, but not horrible. However, although the injections are somewhat painful, if you do have a lot of fluid in your hip, removing some of the fluid and relieving some of the pressure may actually give you some immediate pain relief.
Happy Holidays! Let us know how everything goes. I hope you are able to find some relief from your hip, at least.