Hello And Thank You! Just A Little Background... I Am

Hello and thank you!
just a little background... I am 52, partial hysterectomy in 2009, working ovaries were left behind.
when I started experiencing hot flashes and mood swings I was put on estrogen. I have been on a low dose estrogen for approximately three years. Recently I ran out but it took a couple weeks to get in to see doctor and renew, however during this time I have been suffering with the what my dr says is normal mood swings and hot flashes, over tiredness and no energy. He renewed my prescription thankfully but I was told it could take a while for the medicine to start to take effect is this true top the best of your knowledge or will I be continuing on feeling this way a while? I cannot remember how long it took to start working.
thanks