How quickly do babies movements get stronger? I'm 18 weeks. Last week I felt tickles/bubbles,…

How quickly do babies movements get stronger? I'm 18 weeks. Last week I felt tickles/bubbles, earlier this week I felt a big bubble near the front like it had rolled over (not gas ;-)), yesterday it definitely felt more like proper movement, by last night I was laid half on my side so my belly kind of sat to one side and OH put his hand on my hip/stomach on the slimmer side opposite to belly (it's hidy place during scan) and felt movement. I'm now worried this has changed too fast and I'm concentrating on the wrong things? I know they grow quickly but that's quite a change in a little over a week! What's 'normal'?!