ques here... can supersets be done on a regular basis? or izzit done once in a while to give ur muscle a shock?

juz pass my 12th week of training, thinking of changing routines abit..

protein blends product:

myofusion vs Syntha 6, which one dominates the other? i tried searching for info online but both looks the same to me. So, users of these product in the forum, can u share ur experience?

any reliable local online supp seller (other than ego nutrition)?

questions:

squat: its my 1st day of doing squats with a barbell and with back is straight the whole time... but after each set i feel my lower back worked as well, is this normal or i've did it with bad form?

clean: 1st day doing this also, i felt my wrist is being stressed when the bar is on my shoulder. Sumtimes after the pull i will loose balance forcing me to take a step forward. Ways to avoid this?

madness..