I see the 1795 Marriage on FreeREG, Bachelor/Spinster.
But this is interesting a Baptism same Church;
PETER Plummer 24 Jan 1796 to PETER/SARAH
Mother Late Sarah Greenthree Spinster
Did the Vicar make a mistake with John/Peter?
Then we have;
HENRY 4 Aug 1805
JANE 6 Nov 1808
Parents JOHN/SARAH nee Greentree
Plummer is quite a common name in Norfolk and John/Sarah are hard to trace.
It is possible JOHN Plummer was buried 18 Dec 1810, St Edmund, Norwich age 36 (1774)
The there is a Sarah PLUMMER/John HILL Marriage 3 Aug 1815, St Giles, Norwich
Both Widowed*
May or may not be your John/Sarah.
Peter married Mary GARNER 15 Jun 1818, St Nicholas, Great Yarmouth
He died 1855