The fact that he kept mentioning that he's in school, yet spells like that is what worries me. Anyways....
Pretty much everything has been covered here that I was going to mention, and I'm going to agree with Robbo et al that I have always been told/have always read (eg. Men's Health, websites, protein shake instructions, my doctor brother) that you should ingest a portion of protein within an hour of exercising.
However, what I have noticed recently is that although you may feel safest doing weights you're comfortable with, if you want to bulk up you're best off increasing the weight you're lifting every other week. Also, don't worry about doing less reps, you'll soon catch up. Say you can do 12reps on 17.5kg, bump up to 20kg and do 8 instead, or even 6 if you struggle. (Based on 3-4 sets)
For months I wasn't seeing much improvement, but that's because I was lifting relatively the same weight every time, predominantly because I was worried as I didn't have a mate to spot me. As a result I stopped gaining muscle. Now that I have started upping the weight, I have began putting muscle on much quicker than before. So to those of you like Dskize who are relatively new to weight training and want to gain some muscle mass, like I was about a year ago, either get a buddy who will spot you and encourage you to lift more or don't be afraid to ask another gym goer to spot you.
As for my diet, I currently drink 1 protein shake in the morning, as my body has been repairing my 'damaged' muscle tissues over night, one after my work out, and one a couple hours before bed. That adds up to approx 70grams of protein, and the other 80g I gain from eating small meals throughout the day. (I have been told to base this on 1 gram of protein for every pound, and I weigh approx 145-150lbs).
Also, in terms of paintballing, and general fitness/health, make sure you work your core muscles. Don't just do sit ups and crunches, but get on the gym ball. You may look a little silly at first, but you'll feel the results straight away. Building up your core muscles promotes injury prevention and also helps you lift more if you're using free-weights. It also means you'll be able to snap shoot faster