Choking sensation / lump in throat

I have not been feeling well for about a year and it all started when I went off of my birth control pills of 7 years. My symptoms included: night sweats, anxiety, panic attacks, heart palpitations, dizziness, fatigue, slight weight gain, mood swings, lack of sex drive, irritable, lack of concentration, and shakiness, as if I haven't eaten (blood sugar tests fine).
I did an EKG and event monitor for the heart palpitations and those came back with no findings. I also blood work done and an ultrasound for the thyroid and those came back within normal ranges as well. The only positive finding for blood work was an ANA, further tests showed positive for RNP AB, SER, QL. And no one ever gave me an explanation for this. Time went by and a lump is now present in my throat directly under my chin. The heart palpitations have not gone away and now I have a choking feeling in my throat. Since the thyroid tests came back fine, what could this be from? I also have a "hunch back" and my left shoulder is curving forward rapidly. I have started to wonder if this could be causing the palpitations and choking feeling? But then again what would the lump be from?

Thank you