Can using a home fetal doppler harm my baby and is there a limit of use to be safe I'm 16 weeks preg?

Unlikely an issue. The past studies of doppler use have shown no negative effects.If repeated studies take up your time and take you away from other productive activities, i would consider it more a negative to your lifestyle than a problem for baby. This pregnancy will pass and there are many more issues to deal with than watching baby float around in the womb.