how old are you first off ? 3 months is not enought time to tell if you are going to get big or not but it is s great start
try going simple
diet
training
supps
rest
I know that you have heard it all befor but really stop and look at what you intake in a day get your real food in order for 1 week ahead of time have a meal plan that tells you what to eat and when when you have done this for 7 days go look at the caliorie, protien, fat,carb totals for each day as well as the entire week then add in your 3 tp 4 protien shakles and 1 to 2 weight gainers a day then of couse add in your other supps like creatine glutamine amino acids and thing like that
I will be willing you are not eating as much as you think you are hell I wasn't untill I started logging all I ate and I am only 5'9" and I am 205lbs right now and on my way to 225 I hope !
here is what I need to know to make a better guess for you
1 how old are you
2 have you only been lifting for 3 months or for the last 3 months solid ie have you lifted befor ?
what are your goals
4 what does your current wprk out look like ?
hope I can help
shiko24