Worried and anxious!!

So I’m 19 weeks with baby number 4 and I still haven’t felt movement from my little baby! And with my 2nd and 3rd I know by now I was definitely feeling them wiggle and move around! This pregnancy has been very difficult compared to my other 3, with being in hospital due to the server sickness and the constant being tired, breathless, having rapid heart race and low blood pressure! I’m just worried the baby could be struggling in their or it’s not getting enough to move around! I’m just so nervous my 20 week scan is in the 1st October so I’m just hold out and hoping all is well!