Movement in upper stomach but only 6 weeks

Br

So I am about 6 weeks pregnant and this is a back to back pregnancy where I just gave birth 6 months ago. I keep feeling this weird and uncomfortable movement in my upper stomach. Its typically at night when I turn from side to side either laying down or sitting. I know it’s not kicks quite yet, but being back to back pregnancies it worries me that my internals aren’t quite back to normal. Has anyone else experienced this?!