Hi Alisha!
Congratulations on your upcoming vacation to Walt Disney World, I must say that I love the fact you are getting a head start on planning your trip! All Magic Your Way Tickets will only expire 14 days from the first day you have physically used them at one of the parks, unless you add the No Expiration option in which case they never expire. Yes, you can absolutely order your tickets now and you will be good to go come May. I highly recommend ordering tickets through Undercovertourist.com, they have great prices, free shipping (Canada included) and have excellent customer service.
It is also not too early to order your PhotoPass+ and a great way to save some Disney dollars by taking advantage of the
Disney's special PhotoPass pre-arrival discount. Once you have placed your order you will receive in the mail a disc containing some magical Walt Disney World images, plus your voucher to redeem for your PhotoPass+ card and lanyard. Make sure to put this in a safe place because you will need to have it with you in order to receive your PhotoPass+ card and lanyard in May.
I hope this was helpful, Alisha! Please visit me again if you have anymore questions or need advice while planning your upcoming visit to Walt Disney World.
Have a magical vacation!
Mandy