Google Mail bug?

I have this weird thing that happens with my google mail. My husband thinks I have just messed up my computer, and in reality, it's not a big deal problem. When I get spam, I go to the spam box, either choose all or check off each one, then hit "delete". It always loads but never deletes. I have to go to my inbox, then back to the spam box and hit "delete forever" again and even then, sometimes it does not work. Usually by the third time, they will all delete. Weird problem, not a big deal but annoying nonetheless!