Hey Ark94 let me see if I can give you some information that will enable you to at least ask your doctor some more questions that are pointed and will get you some answers so you dont feel left in the dark about what is going on, or even scared. And that would be a normal feeling btw.
Let me preface this by saying that I am NOT a doctor and this is NOT to be considered medical advice.
First - 20 mg of creatine is overkill. 5 mg is plenty for someone who is under about 200 lbs IMO. The rest could be stressing your system. However, creatine is processed by your kidneys, not your liver. One of the levels that may have been tested is your Creatinine. Creatinine is a breakdown product of creatine. A serum creatinine test measures the amount of creatinine in the blood. This test evaluates kidney function. If kidney function is abnormal, creatinine levels will increase in the blood, due to decreased excretion of creatinine in the urine. IMPORTANT: Creatinine levels also vary according to a persons size and muscle mass.
IMO 2 liters of water per day isnt enough. I would double it. This may help to flush your system of some of the creatine build up from taking too much.
Are you taking any beta alanine? Depending on the bloodwork panels that were ran you should have an ALT number, AST number - these are both liver function tests and are indicators of liver disease. ALT is an enzyme involved in the metabolism of the amino acid alanine. If you are taking beta alanine, it could cause your ALT number to be considered "high".
Ask your doctor if he can prescribe a liver cleanse for you. If he doesnt want to, but doesnt say that there is a risk in you taking one, you can get a milder version at your supplement store. Liver Aid can be purchased at most Walmarts.
Also keep in mind that most blood tests have indicators that tell you the normal range based on age, and whether a level is high or low. But if it is dramatic, it will usually also say ALERT by it. Everything is indicated with numbers. So if a level is high you will be able to see how much higher than the range it is. So because a level is slightly high or low does not mean that it isnt something that can be corrected easily.
As Joe D said, alcohol can play a role in liver function. You said you dont drink alcohol so I wont discuss that further.
You asked about your protein powders. Your bloodwork may also have a test called Total Protein. This is a test that measures the total amount of protein in serum (serum is the fluid portion of blood, without fibrinogen). Total protein is a rough measure of serum protein.
Protein measurements can reflect nutritional state, kidney disease, liver disease, and may other conditions. If totatl protein is abnormal, further tests must be performed to identify which protein fraction, and then which specific protein, is abnormal. Serum proteins are grossly separated into albumin and globulins. Meaning total protein equals albumin plus globulin. Those specific tests are generally included on your bloodwork as well.
Make sure that when you get the bloodwork from your doc, you get copies of ALL the panels ran. They may have you sign a release to get it, but either you or your parents should sign it and get the entire paperwork, not just a one page analysis. This will enable you to see a breakdown of everything that was done and what all of your levels are.
IMO you should follow the advice of your doc after talking with him about this. Dont be afraid to ask him pointed questions. He is working for you. Obviously treat him with respect but answering questions is part of what he should do. I wld suggest you take a parent with you. Two people listening to answers is usually better than one.
Also - if you dont feel that he answered your questions with confidence and knowledge, get a second opinion. Go see a specialist.
The most important thing to remember is that you only get one liver. Treat it with respect. I hope this helps.