My pic keeps changing sizes

Hi I am using an url from photobucket.com I resized the pic there down to 25%. After resizing it is permanent. However, sometimes when i post the pic is poster size!! Then i have asked someone to check it and it is back to normal. Anyone out there know why this is happening? Any suggestions?
thank you in advance

Your picture still looks fine to me

Could it be that the larger version is in your browser cache and it is coming from there?