Water Blisters On Face, Forehead, Chin And Jaw, Liquid Filled. Allergic To Pollen. What Is It?

Hello, I've been having these little water blisters on my face for the past 8 months (weirdly enough its only on my jaw and goes up just a little on my face, never on forehead or anywhere else), they start by being a little itchy then a water bubble (blister) forms. I've seen an allergist and I'm not allergic to anything I eat but I am allergic to pollen, grass (seasonal allergies) I've also seen a dermatologist but at the time of the appointment I did not have any blisters (they appear 2 to 3 times per week) so the doctor could not treat me (she gave me a cortizone cream which does not work at all). I usually pop the bubles unwillingly by scrating and water litterily comes out of them and 2 days later they dissapear but leave a little spot on my face. I tried analysing everything: when it happens, how often, is it my period time etc.. but I found no patern or anything that can explain why I get these blisters on my jaw & chin area. I don't know what to do anymore, these bubbles are scaring my face. help please