Mushrooms? What should i do

I gave my sealed terrarium to my neighbour for a couple of weeks while on holiday. When I got it back there weren't any mushrooms but a few days later they sprouted! Have had this terrarium for a couple of months and never saw a single shroom. Do I pick them out or does the whole thing need to go? Any shroom experts know what they are and if they're safe to handle? Th substrate is growtropicals – terrarium. "Premium range", peat free