At two weeks post-op, you probably feel pretty good, have little remaining swelling or bruising (if you had any at all), and are able to do everyday activities without much limitation.
However, you should not be working out, lifting heavy objects, doing repetitive activities with your arms or upper body muscles, or doing any sort of vigorous activity that could open up a tiny, incompletely-healed blood vessel, and require re-operation for evacuation of breast hematoma! Most bleeding after breast augmentation occurs between day 10 and 27 after surgery, so you are still at risk for bleeding requiring re-operation for up to two more weeks. If this happens, where will you go, and who will you trust your breast re-operation surgery and results to?
So can you travel? Sure, but you cannot lift your luggage to the overhead rack; you should not even be carrying luggage, especially over a long trip. No hiking, biking, or excessive exhausting activity. Exposure to exotic bacteria in an incompletely healed pair of scars--*do you play Russian Roulette?
Also, you are still at risk for developing blood clots, which can be suddenly fatal, for up to a month after surgery.
Why is it that you want to risk your results or your life for this bus trip now? Please rethink this for your own safety. Best wishes!