Scalp Is Dry. Hair Thinning. Get Red Patches On My Scalp. Itch Terribly. Have Dandruff. Pelvic Ultra Sound Shows Cyst. Treatment?

My scalp is really dry and I`m experiencing hair thinning all over for the last 8 months now. I sometimes get red raised red patches on my scalp and when I get them they itch terribly! And when I scratch them they get this wet texture and when it dries it leaves a very thick yellow/white crusty scab and i have dandruff but all the symptoms seems to have calmed down. this all started around november last year. The spots tend to only raise really bad when my scalps wet. I went to a dermatologist and she said it would pass in a month or so, but it hadnt. I called her back and told her and she said to see a hormone specialist. Went to a hormone specialist and got my thyroid checked and everything was normal. Got blood work done everything was fine but my ferritin but the doctor said it was super low it was 21 but I've been on iron pills for awhile now nothing's changed. I got a pelvic ultra sound they said I have a cyst on my right ovary but was very common. I'm 19 now my birthday was the 17 I'm a female obviously but I've lost a lot of hair and just am desperate for answers. My hairloss seems to be the only thing I've noticed that's been affected..any advice would be appreciated thanks!

Rachel