Pilot reported possibly not hearing the correct heading after ATC gave a immediate turn and low altitude alert.

Narrative

While enroute to Ontario eastbound along V186; ATC gave me a vector of 050 for airway spacing for an aircraft ahead of me on the airway. The initial vector took me towards the mountains north of the airway. After a few minutes; ATC then intended for me to turn back southbound on a 160 heading to rejoin the airway; however I turned to a 060 heading instead which continued to send me towards the mountains instead of away from them as intended. The controller then gave me a descent from 7;000 ft. down to 6;000 ft. which I read back and complied with. After a minute or so; the controller issued an immediate turn to the south as well as a low altitude alert and an instruction to climb back up to 7;000 ft. I complied and reinstated a climb back to 7;000 ft. as instructed. I then rejoined the airway and proceeded as normal.Without hearing the ATC audio of the heading instruction to turn back southbound; it is unclear if the instruction given to me was '160' and I simply misheard him and my incorrect read back was missed; or if an instruction of '060' was given by mistake even though he intended for me to turn to 160. Either way; as the PIC (Pilot in Command) I should've spoken up sooner and clarified with ATC on the heading as it did not make sense to be descending towards rising terrain. Also speaking slowly and clearly on the radios; even when it is busy; could've made it more likely that the controller would've heard the incorrect read back and corrected the situation that way. Overall; there was miscommunication on both sides and more diligence needs to be taken from myself to speak up and clarify things if they do not make sense.