I Feel Weird

For the past 2 days or so I have been having what almost feels like cramping/heart palpitations I'm my chest just behind my breast bone. Also, I don't know if the baby is doing a flip or what but for a few minutes I feel like my organs are being squished. Kind of woozy and heavy. It's very hard to describe... Like something important is being deprived of blood and oxygen. I don't know. I am a FTM   and its weirding me out!  Anyone had this? I'm 24 weeks. Anterior placenta. Maybe it's anxiety? Gosh I don't know my body is nuts.