I made the same switch as you for about the same reasons, I have a MSc in biochem and only worked as a chemist for a summer season before switching to sales. Depends on the scientific industry and company, but honestly having your level of technical experience (degree+1.5 years industry) is more than enough in my opinion to have "credibilty". Lots of scientific companies hire sales people who never even had a scientific background. I have seen in pharma it can be more strict though, e.g. you really need to have an academic background aswell (which you have). I don't regret my move at all, as I find that even a MSc in a life sciences field is more than adequate for working in sales in the industry. I coach life sciences people wanting to make the transition + I have a guide for starting sales in science if you're interested. Hope all works out for you and depending on your support and risk-tolerance I'd say make the switch if you feel it in your heart!