Martin, I would ask you the same thing the Hulk has asked you, " When do you let your muscles rest and recover".
As a beginner you are always very keen, personally I would have dropped you back to three days a week, training alternate days, sticking to the basic exercises for bodyparts and most important taking your time to learn to do the exercise properly to avoid injury.
Your body needs a days rest in between each workout as the muscle fibers are torn a part and then mend and add more fibers during the rest period.
If you train 6 days a week you'll burn out very quickly and your muscles wouldn't grow at the rate you would like thereby making you depressed and more likely to either give up or go down the wrong path in supplements.
Now that you have had 2 months training it's time to get the gym instructor to reset your routine looking at starting a split routine for different body parts so that you don't train the same parts 2 days in a row, that way you can spend more days at the gym.
As far as supplements "whey protein" would be the only thing I'd recommend along with a good diet also changing from the usual 3 meals a day routine to 4 - 5 smaller meals to get you ready to accept a more healthy and larger food intake as you progress.
Look around the gym and see if you can find a training partner who maybe interested in helping you, also keep a training diary on what weights and exercises you are doing, I found this a very helpful "tool" as you can see what progress you are making and not judging your progress soley by what you see in the mirror.
One rule I learnt regarding supplements, " If your urine is a bright shade of yellow, your body is passing what your body can't use, therefore your'e wasting money on taking supplements your body can't use", spend that money on better quality food.
Good Luck and keep pumping.