My son did the same thing before he was colicky. I looked it up and it said that when they're really young they haven't mastered how to poop essentially. like they don't know what muscles to use. My son would get belly aches and would try so hard to poop but just didn't quite know how to yet. Gripe water and gas drops helped us a ton. I think it's too soon to say definitively that she has colic. I'd keep an eye on her and write down the days/times to show doctor but like I said it has to be on going for several weeks before they'll deem it as colic. Hope she gets relief! My son lived on gripe water and gas drops for 3 months. He also has a milk allergy and reflux.

thanks @towens921 the reason why I think its colic @jacesterlingsmommy is she goes through this high pitch crying fit and starts pushing and tightens her belly its happened for 2 nights in a row

Gripe water does help, can have at any age. My son went through the colic stage but according to the requirements to have it baby has to cry predictably for at least 3 days a week, 3 hours a day for 3+ weeks. I see your baby is still younger than that. The first few weeks are tough. They also make probiotic drops that help with colic.

Gripe water works wonders. She may have to be alittle older to get it though