need some plant help!!!

I was going to repot my shamrock plant this morning 'cause it hasn't looked since Christmas time. I asked Jeremy to move it onto our little glassed in front porch this morning and this was growing in the middle of it. (They look like fuzzy yellow mushrooms, but very thin on top). They weren't there last night, but are clearly there this morning. The second pic is of the "stems." Any ideas out there as to what they are and, more importantly, how I should proceed???????