Call emergency services. When this happened to me the fire department told me not to open doors and windows just to leave. They brought what they called a “sniffer” and located the source in like 30 seconds. My furnace backdrafted when the furnace was on but the outside temp got warm quickly and it was incredibly windy.

The kids sets I bought from them this year are just as spectacularly shiny as the baby spoons I bought 5 years ago and used daily. I hope it’s just whatever batch you got. The kids stuff is still solid.