I know when spring is in the air since these little blisters with blood or clear fluid start happening in my cheeks. If I use my fingers to try to pop, they often expand instead of popping. This is the first time in the 20 or so years I've been getting
Large blisters after I burned the soles of my feet walking on hot pavement. Sorry if it's not the best quality - this photo was taken in December, 1999.