Actually, unless you were in the process of travelling for the entire time, a better phrase would be: I have been gone somewhere the last few days OR I have been gone the last few days This assumes that you just got back. If you have been back for a while, you would tend to say: I was gone for a few days.

It depends on whether the recent event relates to the present or not. "I've been (somewhere) for the last few days." - it doesn't make logical sense to say "I've gone"(=I am not here now) and also report it in person. This explains your previous absence, the fact you are back, plus your new-found experience of where you were. This describes the present. "I went somewhere for the last few days." - this only refers to the past. It doesn't impact on the present. When you write "the last few days", do you actually mean "recently"?