The lump may be a collection of fluid that can be aspirated with a syrine and needle. You plastic surgeon will be able take care of it quickly when you see him or her. The other possibility is that it is some fat necrosis. Either way, a visit to you surgeon would be most helpful.
Seroma is a fluid collection that can form under the skin after lipo and frequently recalcitrant to massage. It may need to be aspirated. A clinical exam can usually diagnose it if this is the case.
This is normal and with time will go away.Heat and massage will get it to go away sooner.These lumps are sometimes tender but patience is all you need.
You should follow up with your plastic surgeon. He or she can address your concerns and make an accurate assessment in determining the problem. Arnica is not going to help.
You need a proper medical assessment.
Best of luck,
Mats Hagstrom, M.D.
I suggest radiofrequency treatments like venus legacy to help loosen the scar and decrease the swelling. Botox/dysport can relax the neck muscles to further improve the healing. If after 3-6 months there is still a lot of tightening and irregularity, only surgical treatment can improve this. Best, Dr. Emer.
After reading all your postings you have options. If staying in USA try to find a PS who will take over your care and offered aggressive lymphatic massage with external ultrasound (I charge $100per session minimum of 5 sessions). Or find a KyBella injector to inject KyBella. May need 3 sessions at $800 per session. But finding KyBella today is very difficult since Kythera (owns KyBella) was purchased by Allergen (BOTOX owners) the $$ have not exchanged so there is NO KyBella available! Or might try injections of PIT to help improve the lump, fee $200 per session. And finally you can fly back to Dominican Republic to be treated by your surgeon.