10 week old DS exclusively BF, but could I be giving him tummy ache and making him constipated ?

[mppaw]

DS is 10 weeks old, feeds very very well, but hardly goes a poo.
I can tell when he is going to go, as he farts and it really stinks and he gets really miserable, but this goes on for about 2/3 days before he finally goes, and when he does, OMG it is massive and comes out the top of his babygrow !!

He has gained 5lb in 10 weeks, so I think my milk is ok, but could I be giving him tummy ache and constipation ?

This is normal, don't worry. DD1 used to go for a week at a time between poos, and then produce a devastating one. It was awful waiting for it to strike! But it was definitely all fine and not a problem for her, just a change of clothes issue for me.