I'd like to get lip Injections but my pain tolerance is super low, any suggestions to help with the pain?

Lip injections do hurt! Luckily, if you go to a good and experienced Medical Spa or Cosmetic Surgeon, they will have the option of a dental block for you (just like at the dentist). This will make you feel much more comfortable and numb than just topical numbing cream. You will feel initial pinches from the injections from the dental block, but it is significantly LESS than you will feel with lip injections.
You can also ask your injector about using small syringes like insulin syringes to help with pain, bruising, and swelling. 
Definitely set yourself up with a consultation and find a nurse that makes you feel at ease and comfortable.
Best of luck from Gravity Med Spa!

The two main ways to anesthetize the lips are to put topicals or carry out some regional nerve blocks.  You can also inject locally but this can obscure the anatomy and may get in the way with the results. Prior to doing the injections for the regional block you can use topicals and ice to further make it more comfortable. Also using something that can create some vibrations can also make the regional blocks even more tolerable.