Okay so I'm not gonna lie to you - everyone's pain tolerance is different so what feels like a 3 to one person might feel like a 6 to another. But I can tell you that with proper numbing, it's really not that bad! Most reputable places will use a good topical anesthetic that they leave on for at least 15-20 minutes, and some injectors even use dental blocks if you're particularly sensitive. The sensation is more like pressure and slight pinching rather than sharp pain. Some areas of your lips are more sensitive than others - like the center of your upper lip tends to be a bit more tender, but again, with numbing it's totally manageable. I'd say most people rate it somewhere between a 2-4 out of 10, with the worst part being more of a weird uncomfortable pressure rather than actual pain. One thing to avoid is taking aspirin or ibuprofen beforehand because those can increase bruising - stick with acetaminophen if you really want to take something. But honestly, the anticipation is way worse than the actual experience! The whole injection part is over so quickly that even if there are a few slightly uncomfortable moments, it's really not a big deal!