Your body mass index is 19, which actually suggests that you are underweight for your height. You exercise daily and eat a generally healthy diet - it seems like you are doing all the right things! So the question is...do you really need to lose the weight...?
I understand where you are coming from...my BMI is 18/19. I wanted to be a certain "number in weight" but when I noticed that my body just wouldn't lose anymore, it's because my body is comfortable with how much I weigh now and if that's what it "wants to do" so be it. I used to weight 140 (female, 5'5) and got down to 108. I'm at about 115 now and that's where it stays. I almost CAN'T lose anymore. Don't stress about how much you weigh. Especially when, YES, you're actually UNDERweight. Remember that too. Worry about it, maybe, when you're in your 30s.