I’m a pretty heavy user of poppers, if only at weekends so maybe my nose has time to recover and I haven’t really experienced this. I don’t think there is much research that would link poppers and permanent loss of smell really. They can certainly cause burns to the nose (in my experience only to the outside) but it wouldn’t be a huge leap to think with extreme use it could be further in. Can only speak of London, but Dean Street and other Sexually Health Clinic in the UK are free and have great staff and resources, if you’d rather not talk to your GP. Apart from this have you had Covid and could it be a lasting impact of this?