That is a fun question. The universe is curved, it is expanding into itself. Remember time and distance are variables. If you could travel in any direction out to the edge of the Universe, you will find yourself headed back here again.
I think it is expanding into my garage and basement..
The 4 extended dimensions that are characteristic of this universe have a radius that is expanding from ~ the Planck length into the vacuum. That's because, the universe appears as a phase change of the energy contained in the vacuum. ...as a steam bubble appears in a pot of boiling water. Alternatively, an equivalent way of looking at it is that the 4 extended dimensions are less than the Planck length and shrinking into the vacuum. ... a steam bubble shrinking back into the liquid phase...
Saying that one can return to the same point at a later time after heading out in any direction of space, would mean the space had positive curvature and would collapse back onto itself at a later date. Space itself appears to be very close to flat, which means the travel time would be infinite for such a journey. Space in this case simply dissipates back into the vacuum. Keep in mind that the total energy of the universe at all times is zero, just as in hte vacuum. That means the positive energy of the "stuff" and the negative energy of the gravitational field total up to zero at all times.