Baby heart rate low

So i don’t want to sounds crazy but I am getting worried. I am 23 weeks today. Felt great in the second trimester so far, also feel regular kicks. Today is different, wasn’t feeling good in the morning and I also threw up. Baby also isn’t very active like he always is at this time. Being worried I wonted to listen to his hear beat on the home Doppler and it seems very low. Only about 70 beats. I am really trying not to freak out but I am so worried !