I've been taking 1mg estradiol + 100mg progesterone for almost 2 months. My estrogen levels are still very low, how long will it take to see increase?

Unclear plan. I would clarify with the doctor what you are taking and why you are taking it. The answer depends on the underlying problem being treated. For example, If you have premature ovarian failure then one would base treatment on symptoms not blood estrogen levels. Other diseases treatment could be based on LH/ FSH levels.