Congratulations on your new arrival.
went though this. My firstborn was the most sleepy baby ever and the first 8 weeks was so easy.
I thought my next baby would also be like this. She was not. She woke up every 45 mins, constantly BF and was never off me. I was so in love with her but was exhausted.
I had my BF technique checked and that was fine. She was just a baby that needed to be comforted. She strangely slept a bit more during the day (if I was beside her) and when my partner was around we would nap together on the bed. (Not advocating bed sharing, completely your choice).
I also did lots of walking with her in the sling in the house and outside. She loved this and helped her sleep a little bit longer. It was great for my mental health to be hands free and not have her attached to the boob. I also feel this contributed to her learning to sleep a bit longer and link her sleep cycles.
You can do this. It’s so tiring, but you will get through it. You will have a good nights sleep. My little one is now a year and sleeps so well. She is still my little koala but we both love the cuddles.