I spoke with the local Veterans Service Organization and was told i needed to get a letter from my Physician (VA Dr.) to get my service connection increased. I spoke with one of the nurses on the team and she said to make a request, but the Dr "isn't allowed to write that anything is a result of your service". Is that correct? Am I already starting behind the 8 ball on this trying to get my service connection for my back increased?
You're speaking of what is sometimes called a nexus letter...a document written by a credible expert (usually a board certified MD or DO) that confirms the likelihood of service connection of a given condition.
The nexus letter isn't used so much these days. Many are of the opinion (I am a true believer) that an Independent Medical Opinion (IMO) is what is needed. I guess I'm a fan of the IMO because some 15 years ago I paid to have my IMO done and won my appeal.
Today I urge veterans to have an IMO done for every claim, not just for appeals of denied claims. A professional IMO is nearly impossible for VA to deny. The independent disability doctor knows the language that the bureaucrats have to hear to award a claim and that makes the difference.
Your VA doctor won't do that for you for any number of reasons. The number one reason is that if he or she did, there would be a line of vets out the door to see that doctor.
I refer to a small handful of doctors I've known and trusted for years. If you do not have a well grounded claim, they can not help you. If you need someone to review your records under a microscope and write a service connection opinion, look here https://www.vawatchdog.org/imo-ime-medical-opinions-exams.html