I have to admit that the 52 seems a little small for your size but without more specific dimensions it is hard to know. Some people have longer arms and or legs than others. Others have given you solid advise about adjustments but the one thing that really strikes me is that you stated that a fitting costs $375 in your market. That is really expensive and I am assuming that it is a specialized fitting and not a basic fitting. Basic fittings typically run between $50-$100. I would call a lbs and inquire about the cost of a basic fitting. When you go in, take your extra stems with you. They should tell you if your bike is the right size and if they can actually size you for it. Also, keep in mind that you last rode a bike 5 years ago. You are not as flexible as you were then. It happens. As we age, we have to do more to maintain that flexibility and little by little it disapates. At 31, you are still young but you are no longer in your "prime" athletic stage. Flexibility takes a hit. I would not worry, I would just go see a shop.
The worst case scenario is that the bike is too small. You just bought it used so you will take very little if any of a financial hit in selling it. Getting the right fit is essential though whether it is this bike or another one.