Hi Karen
If you kept a copy of your previous claim then I would use that as a template but up date parts of the form where your condition has deteriorated. Don't forget to send in any new additional supporting documents if you have any.
Check out out 'Members Only Guides' for PIP they are well laid out and easy to follow which should help you with your re-newal pack.
www.benefitsandwork.co.uk/help-for-claimants/pip As to your question 'what are the chances of keeping my award even though my health has got worse', fortunately I am not a betting person so unable to give you any odds, all I can say is that I have come across some claimants who have been awarded zero points from an assessor but come away with over 30 points at a tribunal, which happened a few weeks ago, if I could see into the future I would do the lottery, best of Luck.
Don't forget that if you have any questions then do come back to the forum.