Sleep of my second child makes me regret having him.

I think this is going to be a venting post rather than asking for advice because I honestly do not believe that anything can help.

I have a 5,5 month old boy. This is my second child. The first one was a miracle baby that slept through since he was a 3 months old and we only needed to pat him down. My second born since the beginning I have to constantly hold him and bounce on the yoga ball. Right now he is 5,5 months and instead of the recommended 3-4 naps we have 6-7 naps that all last 20 minutes each. So, our ww are all over the place as well. I tried 1.30/1.45/2/2.10/2.10 it didn’t work, still 20 min naps. Right now we are doing 2/2/2/2.20/2.20 and it’s also not working. He wakes up several times a night. Gets up for the day at 5 am. Goes down around 7-8 pm. And he is sick now, so I literally have been holding him non stop for 32 hours now. I cried like crazy today. Because I m exhausted? My back and ass are killing me from bouncing on the yoga ball non stop. It’s honestly making me constantly feel like I made a mistake having second child. I love him and my life, I just feel like I m pouring from the empty cup for the past 6 months. Please tell me something encouraging, I am all alone, the only help is my husband who works and occasional babysitter.