5 1/2 month old waking up screaming

Ok so my LO starting sleeping 10-12 hrs at 4 months and now the past 2 weeks he wakes up 2-3 times a night screaming. I try to sooth him back to sleep but after 5-10 mins I end up feeding him and he goes right back to sleep. He also would take 3 one and half to two hours naps and now he I can only get him to take 30-45 min naps and sometimes longer if I hold him. Is this happening to anyone else? What have you done if so? (Picture because he is just to cute not to share)