Why type of stinging insect is this?

The other day i was sitting on my porch which is concrete and noticed a horent/yellowjacket type insect coming in and out from under my doormat i didnt not investigate until my boyfriend came home form work and had him move our doormat. when he did we saw a collection of tiny pieces of green leaves put together in a tube like design in between the crack of the two slaps of concrete. my boyfriend got it out and smashed the single insect inside it was small with a stinger, black with yellow stripes and a fuzzy yellow chest any clue on what this insect is? I am HIGHLY allergic to yellow jackets and have recently been stung by a hornet..we have had several hornets inside our home and are surrounded by woods/plants i am a renter and has asked my landlord several times to take care of the problem he as "sprayed" around the outside of the house and hung a horent catcher..obviously this hasnt worked