Getting tax back?

i am trying to find out if I could get tax back on the following scenario:

I finished work at the end of March this year 2017 and drew a small pension pot which I didn’t know about, hence finishing work a year early. I paid emergency tax but claimed some of that back which I got in June. My question is if I have no other earnings till after April 5th 2018 would I be able to claim the remaining tax back? My state pension and others could start in February 2018 but could defer these till after April if it means getting the remaining tax back.

would welcome your help.

Thanks