Baby 4 weeks sleep feed routine

Hello, my newborn son, is now 4 weeks old. Until he was 3 weeks he had the perfect feed and sleep routine. Feeding every 3 to 4 hours during the day and 4 to 5 hours during the night. His feeding sessions were okay, around 20 mins in total.

Suddenly, this changed 2 to 3 hours during day and night. and he feeds so little around 5 to 15 mins. I think that this changed because our in-laws came to stay with us, and we might be paying attention to him much as before.

What do you think ? am i expecting too much to have a good routine after 1 month or is this completely normal??

thanks.