Thank you for your question. Usually it is not recommend having lip injections while you are suffering from fever blisters. Patients are advised treat these fever blisters with an antiviral medication to prevent them from happening before or during the procedures of lip injections. Moreover, popping your blisters can cause further complications. I recommend you get in touch with your injector and discuss your concerns as soon as possible. All the best!
Any blister that develops shortly after lip augmentation could imply that you have developed a bacterial or viral infection that would require appropriate antibiotic or antiviral medicine. I suggest that you follow-up with your doctor immediately to determine if such treatment is needed.