Of all the + plural form of noun

"Of all the pains and sufferings our family had to go through, one of the most unbearable ~~~."

Hi

"all the pain and suffering" is the phrase I initially tried to use, but it seems a bit awkward when I put "Of" in front of it, so I was wondering if it's OK to make the two words plural to make sense in the above sentence.

I want to talk about one of many pains (or difficulties) the family had to go through. That's why I wanted to started the sentence with "Of all the"

Thanks in advance.