Do I have iron deficiency? How can you usually tell?

Really tired lately [i wake up even exhausted some days] My hair has been shedding for over a month [it varies in extremity,im not talking bald though], PMS has been = worst cramps ever last couple times, quite pale [not sure if thats cos havent had much time in the sun, but I dont look healthy], craving for crappy foods like scrambled eggs with ton of salt&tortilla chips. Been off my usual fitness level in exercise [i didnt go for 2 weeks&it was hard getting back into it]