Denial is Not a River in Egypt

I want you to read your own words for a starter: "I am a heavy drinker but not an alcoholic. I am 20 and I get drunkish 4 or 5 nights per week." And again: "About half the days after I get drunk I am very shaky the next day." And lastly: "I know that I am drinking too much and I need to cut down eventually but for the time being is this shakiness that I get half the time indicative of a serious problem I need to worry about."

If you are experiencing neurological symptom like fine motor tremors after drinking, you are experiencing withdrawal symptoms! Hel-lo! Just because symptoms are sporadic is no reason to dismiss them. There are many variables that are possibly interfering with constant symptoms (what's in your stomach when you drink, fluctuating body weight and fluid retention, etc.). "Eventually," as you say, you might develop Korsakov's Syndrome, a permanent neurological disorder where your brain shrinks in size, and you'll shake ALL the time. Would that convince you that you have done damage? I have shared this elsewhere, but several of my high school acquaintances developed fibrosis and cirrhosis of the liver by age 20, after five years of weekend drinking. Of course the 'weekend' expanded to drinking from Friday night to Sunday night, daytimes included. Your words reminded me of one of them, who used his belt, looped around his shaking wrist and pulled it around his neck, to 'hoist' a shot of whiskey to his lips after a heavy "bender."  It took a suicide among them to get them to stop drinking and head to Alcoholics Anonymous meetings. They were clean and sober 30 years later at our high school reunion. News flash! Your description indicates that you too should attend A.A. meetings ASAP. Also, get a medical check-up and tell your physician what you've shared here. It's confidential, and you need to know your medical status from a medical doctor also, because you are clearly in DENIAL about your condition.