Baby movements

Ash💋💋
Ok so I'm still confused on how far along I really am.. Going off my LMP I would be 18 weeks 2 days but due to his measurements they changed my due date which makes me 20 weeks 5 days.. So I'm not sure really if this is movement that I feel.. At the bottom of my stomach at times I feel like little nudges but you can't feel it from the outside.. Then at the top of my stomach I feel little tickels at times.. Then at times it feels like little bubbles popping.. Is this my baby moving around in there.. This is my 1 st pregnancy this far along so don't mean to sound uneducated.. normally at my appts during ultrasounds or when they are listening to heartbeat he is really active and moving around.. I go for my anatomy scan on the 23rd so I will know for sure whether they are going to go with my original due date of April 14 or keep it at March 28.. Help guys I want to be excited about his movements.. Lol