Struggling to differentiate between aspirated and unaspirated consonants (k vs kh) on recordings

I’ve been recording myself reading out loud to monitor my progress, but when I replay the audio, I can't tell if I’m actually hitting those aspirated consonants correctly or if it just sounds like a muffled 'k'. Is there a specific mouth shape trick for the 'kh' and 'gh' sounds in Bengali that I might be missing? I want to make sure I don't cement bad habits before I start practicing with a tutor on Chickytutor.com.