Side sleeping

So my daughter and I, for the most part, have amazing days together. The only bad area is naps.

She's 9 Weeks old...and her naps are only 30-45 minutes long. She takes about 3-4 a day. I swaddle her and put her down drowsy but awake and she falls asleep with me rubbing her chest. But she always wakes up 30-45 minutes later and she's always crying/screaming and yawning. Clearly not getting enough sleep.

Today I put her down without the swaddle just to see and she immediately flipped to her side and fell asleep like this for 2 HOURS I actually had to wake her up. The entire time I sat in the recliner next to her crib and watched her because it made my anxiety go crazy... everything I've read says don't allow this!

Well...all I can say is she's so happy and she finally got a real nap.

Should I continue allowing her to sleep like this for naps?? I would check on her constantly obviously...plus have monitor on her...

Help.