Personal Trainer, Is it worth it?

As I maxed out my credit card to buy more sessions on personal trainer in my gym, I asked myself, Is it really worth it? I have been working out with my trainer for 2 months now. You could say that I am pretty committed. I work out 3 times a week or even more if I have some free time. My trainer told me that I could definitely see results in 3 months. What worries me is that it has been 2 months and I have not see any significant change in my body. Well, to give you the idea, I am 5'1" and weigh about 120 lb in the beginning. Now, I probably weigh like about 116 lb. I could not see any muscle built from my weight training. It makes me wonder, do I have to much expectation out of these '3 months goal' from my trainer? Is it really worth maxing out my credit card for all these sessions?