Hi ! Your problem looks genuine as you are suffering even after a year of the incident. The pain in the testicle is really sickening causing one to have nausea
and sweating and the pain radiates to abdomen as the nerves of the testes are derived from the abdominal region. After going through your history, I would suggest the following which you might possibly have already taken :
1) Use a properly fitting testicular support kind of under garment.
2) Take a complete course of proper antibiotic and anti inflammatory drug if you have not yet done that.
3) I am not sure of your job if you have to stand for prolonged periods
or not. If it is so, give complete rest to yourself for a few days till the pain is over.
4) It is natural not to have an erection due to the associated testicular pain
5) As you have described that the testis turned a full circle in your hand, possibly it had a torsion which got relived of its own, but gets twisted off and on ( chronic torsion of the testis) giving rise to this kind of sickening symptoms. For this I would advise you to go for a doppler ultrasound
of the testes which will show the vascularity and the nature of the developing cysts in the testis. In case it comes out to be a chronic torsion, then you have to get yourself reviewed by a urologist/general surgeon
for operative fixing up of the testis to scrotum
I sincerely hope that this opinion helps you out and you recover at the earliest.