If there was a blast or bang, it is possible indeed, as the shock wave (for lack of the proper term) continues to expand.
But... what if... outside of OUR observable universe there are multi-verses doing the same thing. In parallel or staggard in space time (unknown) but each expanding within its own “balloon”?
All hypothetical mind you but not outside the boundaries of astrophysical ruminations.
By definition there is nothing “outside the Universe”, with the possible exception of The Creator.