upsampling for a signal
No, if you upsample a signal, its duration (i.e. measured in real-world units like "seconds") does not change. 


If your signal $s[n]$ is sampled at a rate $f_s$ Hz, and it is $N$ samples long, then the total duration of the signal is $\frac{N}{f_s}$ seconds.
Say you upsample the signal by a factor $M$, yielding a new signal $s_u[n]$. It will be $MN$ samples long, but it will be sampled at a new rate $Mf_s$. Its duration is therefore $\frac{MN}{Mf_s} = \frac{N}{f_s}$. You can see that the signal duration is the same as $s[n]$.


It's not clear what you mean by a "shaping filter" in your third question.