Child crying over the night.

My child is turning 7 months next week. For the past 2 night, she would wake up around 3am and cry. Me and my husband would feed her milk, after feeding she start to be sleepy. So we put her down and pat her. After few mins she will start crying again. We are not too sure if she's teething or maybe just a tummy ache. We literally have no idea why she started to cry again. Beforehand, we already changed her diaper. When she cry, she only wants me to carry her. We also tried so many things to calm her down but only succeed when she felt tired. Does anyone know why? Hope I'm able to get answers here😭 #firsttimemom #pleasehelp #advicepls