Krimson is Ethinyl Estradiol and the most common use is hormonal contraception.
However you have not elaborated on why you have been prescribed this medicine, and how long have you been taking it.
Krimson (Ethinyl Estradiol) can cause side effects as sore nipples, breast tenderness, fluid retention, nausea, dizziness and headache.
The symptoms most commonly cease once you stop the medication. However, I request you to consult this with your doctor regarding the dosage and duration.