Bowel movements in the first 2 months

My little guys is a month old (4weeks and 3days) he’s only having bowel movement every two days now and is straining hard when doing so, his last was solid and green he’s pedi says everything looks normal but he’s only pooping when I give him probiotics for a Couple days then he’ll go. Going to keep giving them to him as they were Okayed by his pedi but just curious if anyone else has had this issue and if so what did you do to help it? I feel so bad be the strains so hard he cries and definitely looks like it hurts.(side note his pee isn’t discolored and he’s not running a fever so he is hydrated.