It is never too late to start getting treatment. I agree with the above poster - get a physical scheduled. If you can not get a recommendation for a doctor, you can find the nearest clinic by internet and call the internal medicine department and tell them you want to set up a physical with the first available doctor. Have your insurance information on hand and they will check to make sure you are covered (shouldn't be a problem for a primary care doctor).
Write down your main concerns, and if your medical history is involved, you can write down the dates and names of your surgeries, and a list of any medical problems your family members have. Also write down a list of any medications, herbs, and supplements you take. This will help streamline the process.
Be sure to arrive at least 30 minutes prior to your appointment and bring your insurance card again. Since you are a brand new patient they will have to not only get your account set up/registered for billing purposes but will also have to get your full history which will take time. They may give you a form to fill out to begin the history taking part, or they may have a nurse or medical assistant call you back into a private room to take your history verbally. They will get your height, weight, temperature, blood pressure and heart rate. Then they will leave and let the doctor know you are ready to be seen.
The doctor will speak with you for a bit about any main concerns you have, and then will have you change into a gown (or this may be done first), and will listen to your heart, lungs, belly, and will ask you to lie down and he will press on your belly. If you have a specific concern they will do a more detailed look at that area.
Do keep in mind that your budgeted time with the doctor varies, and it may be as short as 10 minutes. The doc may move very fast which is why it is a good idea to write down your history and any concerns so you can make the most out of your appointment. Again, if your issues are very involved keep it concise - the doc will ask you clarifying questions and may refer you to a specialist who can spend much more time with you on the details of that specific issue.
They will likely order bloodwork to do a general checkup, and may order xrays if you are having pain somewhere(xrays are not painful), and may refer you to a specialist for more thorough analysis. Most clinics have a lab on site, usually on the ground level floor, where you can bring a copy of the bloodwork order, and they will get your bloodwork done.
After your bloodwork/xrays has been drawn give it two weeks, and if you haven't heard anything from the doc, give them a call to get your results.
Its never too late to start taking care of your health, so good for you! It can make a big difference. Docs know that people are nervous so don't worry. They will walk you through the process and let you know the steps.