Sleep Issues

My 3.5 month old has started sleeping through the night (was up for a feed somewhere between 3-4 am until about a week ago, now sleeps until 7). However, putting him down for bed or even for naps have become quite an ordeal. He cries and screams just about every time and takes quite awhile and often multiple attempts to calm down and fall asleep. We try and look closely for tiredness cues to not let him get overtired. We have moved his bedtime up a bit (and added a dream feed then to keep his intake about the same every day now that he’s not waking up in the middle of the night). We try and stick with a routine including having him nap/sleep in his own bassinet with a dark room and noise machine, trying to put him down drowsy but not asleep, etc. It is just such a struggle getting him to sleep every time and breaks my heart to hear him scream. Sometimes I swear he starts crying the second we walk into the bedroom. Is anyone else experiencing this? What can I try differently? Or Is it just part of the natural sleep regression common right now and he’ll grow out of it? It’s just so frustrating so any advice is appreciated!