Too much sleep??

Anyone else's baby sleeping a crazy amount?? Ever since he was around 11 weeks old my baby has slept 12 hours straight through the night. Will usually go to bed at around 6.30pm and wake at around 6am. Recently his bedtime seems to be getting earlier. When I put him down for his naps through the day and in the afternoon, I don't like to wake him up as I believe it's good for him to sleep if he needs it and just wake naturally. Usually his naps will only be 30 minutes long during the day, but recently some days they can last for hours. He will also go down for his afternoon nap at 4/5pm and rather than waking up for an extra hour before bedtime he seems to be sleeping right through. His sleep pattern seems to be all over the place, he's sleeping for a crazy amount of time.. e.g. Last night, he went down for his usual afternoon nap at 4pm (bare in mind he'd only had 3x 20 minute naps through the day so he was pretty tired) - he didn't wake up for his 5pm bottle he stayed asleep the whole night until 3am. He had a feed and bum change at 3am then went back to sleep around 4am. He then slept through until 7am then woke up for the day (so he had a total of 14 hours over the night with only 1 wake up). After his 7am wake-up he only stayed awake until 8.15am then fell back asleep until (almost) 12pm - so another 3.5 hours.. he woke again at 11.50am then fell back asleep at 1.15pm, he's now been asleep again for almost 2 hours. He's been having his bottles and bum changes and playing in-between..he's still his usual happy self. But I'm worried that since 4pm yesterday afternoon he's had a total of almost 20 hours sleep?? Idk if it's just him developing and growth spurts etc. Should I be waking him up or is it ok to just let him sleep as long as he needs? I've heard of 4 months sleep regression but if anything he seems to be sleeping a lot more, not less🙈. He's just learned to roll over, he's constantly trying to sit up-right. He's constantly babbling and chatting to us and himself. He's just moved into his 3-6m clothes and is healthy weight. He has 6oz bottles and I just feed him on demand. I'm confident that he's developing on track as he should, but I'm a FtM and worrying incase this isn't normal🤦🏼‍♀️