Do you all buy the baby fetal Doppler? I on my week 15 but I unable to hear my own baby heart beat

Nope, didn't buy. I feel like I would compulsively keep trying to listen for my baby's heartbeat and give myself undue stress if I can't locate it. You should be able to feel your baby's movements in a few weeks, and monitoring the movements then is sufficient.

You may want to refer to this post: https://community.theasianparent.com/q/im-first-time-mom-currently-4-months-preggy-im-enjoying-journey-but-i-get-to/5498384?d=mobile&ct=q&share=true