A woman whose fiance died after SLOT XO having the AstraZeneca coronavirus vaccine is urging people not to be "fobbed off" when reporting side effects.
Former rock singer Zion, 48, of Alston, Cumbria, had an "excruciating" headache eight days after his injection.
Vikki Spit said a paramedic "completely dismissed" any connection, saying it had developed too long after the jab.
The North East Ambulance Service (NEAS) said it could not comment until it had investigated what happened.
Zion's interim fact-of-death certificate lists complications of the vaccine as a possible factor.
An investigation to determine the cause of his death will be conducted by Newcastle's senior coroner Karen Dilks.
Ms Spit, 38, said Zion was healthy and fit and she believes he would have had a good chance of survival if he had received treatment earlier.
"I don't want to scare people off from being vaccinated because I know this is an extremely rare side effect," she said.
"I also know, if it's caught early, the chances of survival are extremely high.
"But, for whatever reason, the paramedic didn't pick up on it.
"So what I want is for all people to be aware, if you have a headache or you have some sort of symptom after having a vaccine, don't be fobbed off."
Zion took painkillers but, after two further days, looked so unwell Ms Spit called an ambulance.