Your urine being clear is GOOD SIGN. You want it to be clear, that means you are getting enough fluids in your body and it is ridding of all the toxins within. You cannot die from drinking the amount of water you are currently consuming.
A spike in LH and FSH (LH surge) causes ovulation, following a suppression of GnRH. Estrogen levels continue to rise following ovulation and the corpus luteum forms, which secretes progesterone in significant levels and causes decreases in LH and FSH levels.
The endometrium changes throughout the menstrual cycle in response to hormones. During the first part of the cycle, the hormone estrogen is made by the ovaries. Estrogen causes the lining to grow and thicken to prepare the uterus for pregnancy. In the middle of the cycle, an egg is released from one of the ovaries (ovulation). Following ovulation, levels of another hormone called progesterone begin to increase.