God commanded them to have children but it does not say God beheld it right then, it does not say "and it was so" following that verse.
Have you got some other verse that shows there was human birth before the fall?
Commanded is the wrong word. 'Be fruitful and multiply' is a blessing and when God pronounces a blessing, it happens. 'he blessed them' Gen. 5:2
And it was so. Gen. 1:30 I wish people would stop referring to every line in the Bible as a verse. There are no verses in the Bible. The numbering system used in the Bible just makes in easier to find words. God doesn't speak in verses. The word of God isn't poetry. 'And it was so' covers everything God did in the 6th day. God beheld everything he had made, and behold, it was very good. 'And there was evening and there was morning, a sixth day. Gen. 1:31 If it was up to me, I would start Gen. 1:31 with, 'And it was so'. Unfortunately they stick it at the end of 1:30 and then people get all confused.
Now this one I can see your point. So I had to look at the Hebrew transliteration and I'm still not sure I can refute your interpretation. I will quote the KJV and then the YLT.
Gen 3:16 Unto the woman he said, I will greatly multiply thy sorrow and thy conception; in sorrow thou shalt bring forth children;....
Gen 3:16 Unto the woman He said, `Multiplying I multiply thy sorrow and thy conception, in sorrow dost thou bear children, ......'
In the KJV where it says 'greatly multiply' both of these translated words are the same word in the Hebrew.
I will have to research this. I think it is possible that this is a case were the Hebrew language uses repeated words and terms that are to give a sense of something other than how it sounds in English.
Like God owns all the cattle on 10,000 hills. Well God owns all cattle on more than 10,000 hills but it's still a large number so you get the sense of what it means.
In this case, "greatly, greatly thy worry/pain and thy pregnancy.....".
We have a member who is talking about learning Hebrew, I wish he'd get busy with that.
There's no need to study Hebrew. They were breeding like rabbits before the fall.