I did a consultation for someone who got a lip piercing and was concerned about how it was healing:

Hi! 8 days ago I got my lip pierced professionally. I was pierced with the standard gauge at 16g stud. My cleaning regimen goes like this: Every morning after my first smoke and breakfast, I brush my teeth, do a 50/50 mouthwash with water and Listerine, and clean the outside with antibacterial soap. When I get out of the shower I do a sea-salt soak for 3-5 minutes depending on how it feels. These actions are per my piercer. After I eat or smoke I swish sea-salt water. I do the morning regimen before bed, skipping the last sea-salt soak.  My problem resides on the inside of my lip where the back of the stud sits against my lip. I'm trying not to panic, but I am known to overcook things when I notice something weird going on on/in my body. What I SEE looks like a small mound of scar tissue; it's not very red and there is no leakage other than small amounts of lymph. I should tell you that this scar tissue (or whatever it might be) is aiding in the back of the stud leaving a mark where it sits. What I FEEL is a small lump under the skin just next to my piercing. If I show anyone what I am feeling, they would not see it as it is impossible to see under the scar tissue. It worries me because I don't want to take it out or get rid of it. It looks pretty and I love it. I wouldn't think it is because my long stud is too short because it sticks out a ways in front.

 

My reply:

You're cleaning WAY too much and damaging your piercing! Don't use Listerine (even diluted), or any alcohol-containing mouth rinse while you're healing. That is no longer advised for healing oral piercings. It seems your piercer is not keeping up with industry standards.

These are the care instructions I suggest you follow (from the Association of Professional Piercers) and you will likely see some improvement if you stop abusing the delicate tissue of your piercing!

Believe it or not, the piercing actually looks pretty normal. And some lumpiness/scar tissue formation can be normal as well.Note that 14 gauge is actually quite common for lip and labret piercings, and you may ultimately find that 16 gauge, is a little thin, and may not be helpful for healing. Though I would not suggest you stretch up to 14 gauge until the piercing has fully settled and healed.

Also, You should give the NoPull Piercing Disc a try. This is exactly the type of situation it was invented for! You just need to be sure that when you add the disc, that doesn't cause the post to be too short. It should be worn with the disc pressed right up against the tissue, but you don't want the jewelry digging in at all. You can order them here or directly from the manufacturer.
If you use it, please let me know how it works for you. I'm gathering data about its effectiveness (all signs point to "it works GREAT!").