Can’t Find Answer to this Metformin Question

hello! i’ve been on metformin 500 2x/day for three weeks now. my BS’s are doing well, but i feel like **** … no energy at all and all i want to do is sleep. i test many times a day, so i know i’m not hypo. can metformin be the culprit here? i had a complete physical and blood work done in november, so i don’t think it’s anything else other than the metformin. (oh, well, i do have a head cold, but it’s JUST a head cold.)

any ideas would be greatly appreciated.