Are there any NI credits available for having had to reduce my hours due to being a carer

I cared for my severely disabled husband for 18 years whilst also working full time. eventually I had to reduce my hours to enable me to take him to appts each week . I was never entititled to any carers allowance or anything else due to my salary , but he got PIP/DLA. Obviously my NI contributions were reduced when i went part time . Can I claim any sort of NI crediits to be backdated to the period when i was caring for him? If so How ? I now find that despite working 38.5 years and never claiming any benefit apparently I havent paid enough to generate a full pension when I reach pension age in 5.5. years

Hi 
You may potentially be able to receive backed credits for the period you were looking after your husband.
However we require further information to know for certain and in order to advise you what action to take.
Please contact our customer service helpline or our webchat service, please find our contact details below:
National Insurance Enquiries helpline
Thank you.