Could it be my baby moving?!

I am currently 15w1d with my second child. I think but am not positive that I felt my baby move a few times. Not regularly but mainly when I'm laying in bed at night. I will poke my tummy and sometimes feel a very gentle rolling fluttery feeling between my pubic bone and belly button. But the last two nights I've been trying to find my baby's heartbeat with a Doppler app I downloaded and when i pressed my phone on my tummy I think I felt my baby trying to move away or fight me off lol. Could this be my baby?