FFT, padding, IFFT and plot in time domain
user3406207: I'm not sure what you're trying to do because I don't know the meaning of your words "wrong" and "right."  But we can say, if you perform time-domain zero padding on an original unpadded $x1[n]$ input sequence you'll produce some longer-length $x2[n]$ sequence. The $X2[m]$ fft of your $x2[n]$ sequence will be an interpolated version of (more freq-domain samples than) the $X1[m]$ fft of your $x1[n]$ sequence.  And, of course, the inverse fft of $X2[m]$ will be $x2[n]$ and the inverse FFT of $X1[m]$ will be $x1[n]$. I hope that helps. (By the way, you were smart to plot just the real part of your inverse fft.)