Well she says this person is a nurse. So this person most likely introduced themselves as a nurse. So they are claiming they are a nurse until it's proven true, right?
If I were to take supplements, which I don't, since I consider it to be pseudo-science[1][2], I would get them from my local drug store which has the german equivalent of a FDA license and regular audits.
[1] https://www.youtube.com/watch?v=29v6rNFjlLI
[2] https://www.theatlantic.com/health/archive/2013/07/the-vitam...
Let's look at it empirically. Among elite athletes, how many take zero supplements? I can't prove that they're getting any benefit but the correlation between performance and the use of certain supplements is so strong that I suspect there's something real going on. (And by supplements I mean real supplements, not PEDS which are an entirely separate category.)
Soon a new world of injections and supplements will be yours if you want it.
Nightmare fuel.