What is wrong with me!

For the last few months I have been extremely tired, from the beginning of the day to the end of the day. For the last few days, I've been getting these horrible headaches on my left side of my head. I've never got headaches before and I don't know what is wrong :( I am so tired and no matter how much sleep I get it's a struggle for me to get out of bed in the morning. Work has been extremely busy all week as well which puts more strain on everything :(