Might be a ridiculous question but .....

I'm pregnant with me first baby 18 weeks and I have no idea what it feels like to feel her move around or kick. But I feel like I might sometimes. Or is she to small to feel and if she is. Then the sensation I feel should I be worried. Feels almost like a slight pressure or pinch in my belly. I'm not big at all as belly wise so I'm very confused and intrigued to find out what the feeling is. Thank you for your help.