Usually your uterus is just hitting your belly button at 20 weeks. I felt thumps above my belly button at 18 weeks, only to find out shortly after I was having twins :)
It could be the baby. With it being your second pregnancy, your uterus can grow faster and may well be above your belly button now, mine was at that stage with my second.
I felt flutters at 16 weeks and kicks by 20 so yes very possible lol. so no youre deff not going crazy! lol
I felt flutters at 17 weeks .. it could be
Every pregnancy is different. You cant compare them.
Just weird this is my second preg and nevrr felt it with first
IT all depends on your body structure and how you little on is positioned. Remember your graowing baby puts pressure on everything else in there so it might be something else. At about 20 weeks your uterus is right below your bellt button