Trying to gain muscle....but really confused!!

I think I'm on 40% protein. Lower carbs. I really only eat veggies and fruits. other than meats. My arms are getting noticeably bigger in the last two months.

I changed my settings to 40% protein, 40% carbs and 20% fat, however, I do much better with higher protein than carbs. If you're wanting to build muscle I'd recommend having higher protein than anything, then you can always change it to suit your needs. Everybody is different

a breakdown of what science (not broscience) has to say about gaining/losing weight and muscle:

http://forum.bodybuilding.com/showthread.php?t=121703981

percents are an inefficient way to look at it; think of it more as meeting macro requirements.

I. meet your target calories to gain weight at the pace you want. this is what i look forward to every four months: switching from the cut phase to the gain phase. going from 2000 calories a day to 2800 calories a day is like a vacation inside food.
II. meet your protein requirements within your calorie goal (research suggets between 0.8 and 1 gram of protein per pound of your target bodyweight; ie, if you want to weight 175 lbs after putting on some muscle, aim for 140-175g protein per day
III. next priority is filling out the rest of your calories with carbs and fat. i tend to go higher on carbs than fat on lifting days, for energy, and about equal carbs and fat on recovery and non-lifting days. i lift in the afternoon; if i lifted in the morning, i would probably have my higher carb day the night before.

to make this work with myfitness pal's counter at the outset, let it calculate how much you should eat to gain maybe 1 lb per week. then, go to My Home -> Goals -> Change Goals -> Custom, and fiddle with the drop down box for protein % until the base % is your target protein amount (eg, 175g). personally, after that, i set carbs and fat to be equal percentages.

of course, because MFP only allows you to set the protein requirements according to a percentage instead of a flat amount, on days that you log exercise, the protein goal will "increase" on your diary. i disregard that, and just keep an eye to make sure i'm closing in on my protein, while keeping a balance on fat and carbs.

edit: medennison123 made similar points, and posted faster than me i feel like his information, while not mirroring mine, is pretty close to what researchers suggest, and is a decent set of guidelines.

i disagree about cutting downt o 12% first, though. in my experience, the 5% between 17% and 12% are miserable, and sometimes a homie just wants to add some muscle and worry about recutting the fat off later. both for the sake of liking having the muscle, and for being tired of eating at a caloric deficit and wanting to eat a monster cheeseburger.

Carbs and protein are needed to build muscle. Not just protein.