How about just getting some blood work? Quit playing the guessing game get bloods and you will know exactly what's wrong. Im willing to bet it's high estrogen, estro builds up with time.

Doesn't make a lot of sense, everything was good while on the deca without using prami when you should have been experiencing the problems you're describing, then you drop the deca and keep the test and you lose you sex drive and slight Ed issues. Honestly, I have two theory's, your deca was test and you were actually running 800mg of test and the 12.5mg of aromasin was keeping estrogen at a point where you could maintain normal sexual function, then when you dropped the "deca" (what I suspect to be test) so you went from 800mg of test to 500, 12.5mg of aromasin was to much for and crashed your estrogen. Not to mention the bottle that said test on it might have been underdosed so maybe you dropped down to 300mgs ew and that much aromasin will most likely crash your estrogen. Thats theory one and the fact of the matter is with many ugls most of the different compounds are just test, they just label them eq, deca etc.

Second would be just you body reacting to the drop in hormones, but it doesn't make any sense really if it was in fact deca blood levels are just slowly declining so there isn't any up and down fluctuation. So in this case I would expect your sex drive to increase.

Any other symptoms? Achey joints, you already mentioned a few that are inline with low e2 ( loss of interest, harder to get erection and hard to maintain) feel lethargic, dry skin and lips etc?

I think the best thing to do is get bloodwork and see where your test levels are at as well as prolactin and estrogen. Maybe you're gesr was legit and your body's just reacting in an odd way right now. Steroids sre weird man you can keep everything the same for the entire cycle and then out of the blue sex drive crashes, or you get Ed problems, or you start breaking out really bad etc. sides just pop up out of nowhere for no apparent reason.