What did i get on my shirt? how do i get it out?

I am so angry because I bought a t shirt recently, washed it, then a bunch of faint purple-ish dots are all over the front of it!! I have NO idea whta it could be. its a guy harvey t-shirt so the back of the shirt has fish on it: purple ish blue fish. could it have bled through? because that has never happened to me with these shirts. I don't even remember the stains being on there before I washed it. Even though I dont know what it is, can you please give me some ideas on how I can get it out??? I tried stain stick but it didn't help, and that normally works miracles! Its a yellow shirt if that helps. PLEASE help I am so mad right now! Thanks