I feel like my 3 month old is behind...

As far as her grabbing stuff, and her hand eye coordination, I feel as if she is super behind. It’s quite stressful. I’m not really sure what all I can do. I have a mat with toys hanging from it for her to kick or grab that sing, but she doesn’t seem to fond of it. I have a bunch of toys for her and I try to work with her on grabbing, but she doesn’t seem to show any interest. What can I do? I’m a first time mom and my fiancé and I are on our own, we have no family it’s only is three. Please help.