Trial and error - beginner bodybuilder

Trial and error. About a week ago when I first began my workout, my arms measured at 14" and my chest at 37". I'm beginning to feel bigger. I do an upper body workout three days a week, and lower three days a week. I take whey protein with leucine and Amplified Creatine 189. I want to start powerlifting/strongman workout style. I was considering getting a harness and begin pulling. What other techniques are there for beginner bodybuilders to increase mass? I will probably go another two or three weeks and do measurements again. feedback is appreciated, please no negativity. thanks

I've noticed I'm feeling bigger, and have also got compliments people telling me I'm looking bigger/wider. I used the same technique to measure my arms, and there is an increase in size. the increase only seems to be about a quarter of an inch, but it's an increase.