I need some help!!!

Oh, I hope you are all on your computers tonight and see this! I have a lot of things ready to go on Etsy. Today for some reason, all of my pictures are blurry when I put them on there. I had this problem about a year ago and thought I had figured it out. Wrong! I've been sitting here almost all day and still can't get a good picture to load. My last attempt was 800 x 800 because I googled and found that worked best. Nope, it didn't. Somebody, please tell me what I'm doing wrong before I throw the computer, camera, and anything else I can get my hands on in the house out the window! What size are your pictures? Thank goodness Idol is on tonight and Brandon is on his way over to watch it with me!

Thank you for any advice you have for me!!! See you in the morning.