Absolutely.  are you currently being treated with one of the DMARDs (disease modifying antirheumatic drugs like methotrexate or one of the Biologics)?   if not, speak to your rheumatologist about getting treated as soon as possible - not only will it protect your joints from damage and thereby protect your future mobility, but it will also make you feel better so you can start eating again, gain some weight and get some energy going. If you are being treated, it's possible that your current medication isn't doing it for you at the moment and that you need to increase the dose, supplement with another medication or change meds altogether. You may also want to ask your rheumatologist for a prescription for prednisone - it can make you feel better quite quickly and tends to make you kind of hungry, as well.  I'd also recommend that you make an appointment with your family doctor to get a physical, just make sure that there's nothing else going on.

Good luck and please let us know how it goes?