Hi. The only symptom that I think you should be concerned about is the "slight neck stiffness"
It looks like you have a
throat infection as suggested by pain while swallowing and the occasional sweating/
fatigue. The neck stiffness may very well be due to
cervical lymphadenopathy due to the infection. These lymph nodes if swollen and painful may restrict neck movement. On the other hand there are some
soft tissue abscesses within the throat that may also present with neck stiffness, throat pain and progress to block your breathing. Hence the reason to suggest that you have this looked into by an
ENT specialist. An oral cavity and neck examination along with a soft tissue
X ray lateral view of your neck will make things more evident.
You will probably need a course of antibiotics, anti-inflammatory medications and oral antiseptic rinses if it is just an infection. If there is an abscess somewhere in your throat then that may be drained through a small procedure in the ENT office.
It appears to me that due to the medications for RA, Sjogren's syndrome and RTA (which suggest autoimmune pathophysiology), your immune system may be more susceptible to infections and may require a more aggressive strategy to treat these infections. Do have yourself evaluated by an ENT specialist for these reasons.
Hope you get well soon. Would be happy to help if you have any other queries.