hi, I missed my periods date.when I came to know as I was pregnant then already I was 22 weeks . now a/c to scanning report it is 34 weeks. but I feel very heavy in my stomach.... sometimes backache....what to do now? whether I was nearer to labour?

Your question is a little confusing. Missing only one period and at 22 weeks ? That does not seem likely unless your cycle was very irregular. It is normal to feel heavy in week 34 as the baby is almost full term. Labor can start anytime post week 37.