Baby won't poo

My baby has been exclusively BF from birth, however due to latch was on bottles till 9 days ago. We'd managed to wean into breast only and have done that since. He did amazingly well, was having 10 dirty nappies a day, ate every 2-3 hours and of those 10, ATLEAST 3 were poos. But yesterday he had one, the day before two and so far hasn't had any today. I'm trying to feed him more as he's 7 weeks and has been eating every 1.5hrs, ive been letting him feed even more than that, but all ive gotten is more wet nappies. He's had 7 wet nappies already but no poos and it's 4pm. He seems happy, tho a little more restless. He's cooing, interacting, smiling, sleeping. But he just won't poo and just wants to be with me and eat constantly. He is so gassy with the extra feeds but nothing. I've rung my health visitor but I'm waiting for a response. Has anyone else dealt with this? Is it normal? Is there ways to help? I've tried all the advice they give you to start, the rubs, bicycle kicks, warm baths, but nothing.