Whickerman you have my complete and total sympathy. I know first hand what that infection is like. Mine got so bad that my jawbone had actually started to liquefy....no word of a lie. It had apparently been building up for a long, long time.
I had been to the dentist several times to complain of discomfort and was told there was nothing wrong! So over a period of a couple of years it just got worse until suddenly an abscess appeared which rapidly spread along my gum line, up the side of my nose and around my eye socket. My eye closed with the swelling, there was no definition on that side of my face because it was so hugely swollen (mine was on the right side too) and I couldn't even touch my tongue on the roof of my mouth because of the pain. It was so bad I was nearly tempted to take a stanley knife to my gums!!!
The dentist had to drill a hole up through my tooth and out through the root to drain the infection and he injected anaesthetic directly into the abcess through the roof of my mouth. That injection was the single most distressing and painful thing I have ever gone through and that includes childbirth. I was unaware that such pain existed without making you pass out. I screamed, I cried, I was beside myself with grief!!! That was followed up by 8 months of weekly trips to the dentist until it was healed enough for an apicectomy, root canal filling and a crown.
So Whickerman I do indeed know where you are coming from and I hope to God that you get sorted before yours ever goes that far. And to have shingles on top of that...oh boy....I really do feel for you!
I send you big ((hugs)) and I wish you better real soon. xxx