3.98 cGPA/sGPA, MCAT tbd, weak EC's

This is my first time posting, so I apologize in advance if I am posting in the wrong place. I am currently a junior majoring in kinesiology and minoring in chemistry, and am hoping to apply this summer. Both my cumulative and science GPAs are around 3.98. I haven't taken the MCAT yet, but have been making around 510 on practice tests, so I hope to make around there on the actual test. I am worried that my ECs are lacking though. So far I have...

-250 hours of volunteering at a children's...

3.98 cGPA/sGPA, MCAT tbd, weak EC's