I'm feeling sharp pains in my pelvic area? Should I be concerned?

That could be a bunch of things. Could be the uterus growing over and out of your pelvis, but it could also be more sinister things. Since you're looking for and asking about this, you are concerned and nothing we say here can help with that. Your next OB appointment should be soon, this is something to ask your OB.

You are concerned so tell your doctor.

Certainly let your doctor or midwife know what you are experiencing if it causes you concern. If you notice it as a sharp pain that comes on and then pretty much goes away when you first change position... standing up quickly for example, it may just be from the stretching of ligaments that support the uterus. Very common, more of an annoyance, than a concern. All you would do is just move about more slowly.

Since this is your third pregnancy, did you happen to have this type of pain with the others? Another possibility some women will experience is SPD, where there may be a bit of separation, or separated movement, at the front of your pelvis. This is sometimes noticed more when you do movements that separate your legs... getting in and out of a car, or bed, walking up and down stairs, for example. Many women find it uncomfortable, others find it extremely painful. There are ways to manage it, if it is determined to be the cause of your pain.