Respectfully, I actually posted what I did as a result of getting bloodwork every other month unlike 99% of people who go off of the way they "feel". When people say they don't need an AI I think it's hilarious, like your body somehow doesn't aromatize testosterone! Not saying you personally, but here's the thing - exemestane just isn't that strong. Exemestane doesn't "crush" estrogen unless you maybe take 25mg a day and already had low test. Some peoples sweet spot libido wise may be higher or lower, but on 750 test a week 12.5mg exemestane eod isn't crushing anything.
Exactly, that's what I was reffering to above. First it was his first week, depending on esters alot of the T was still being release into his blood, someof hadn't even released yet...on top of that hardly any of the T that did release would have had time to aromatize after just a few days and he was already dosing his AI daily...there likely wasn't even much of any excess E at this point beyond what his body naturally has from conversion of his own endo T, so there wasn't the need for an AI but he went ahead with it because that's a pretty standard dose and protocol parroted on the boards. Exemestane has a very short half life and doesn't pack nearly the punch of Armidex or letro especially. In fact Exemestane @12.5mgs EOD wouldn't even have any aprreciable effect on the in between days...so in essence he was probably just crushing what little E his body had naturally from conversion of his endo T, so a very small amount of E, plus he dosed his AI "accidentally" again on the 2nd day and then the 3rd day went ahead and did his regular dose. Guys...we have to remember there is a big difference between "I don't need an AI because I don't get estro sides like gyno or water bloat" The reason being that those two sides are dependent on the androgen:estro ratio so all the extra Androgens are neutralizing much of the effects that the raised estro would show. Like I pointed out, in my 20's I could blast G's of test without any AI or Nolva and not get any gyno....because there were still enough Androgens in the blood. Today, although my body and most other guys who track it will notice they begin to aromatize there Test at a greater rate as they age, but I can still run a gram of T without any gyno and as long as it's Prop or a shorter acting ester I don't really get much bloat, however our libido's are different. That is one of the sides where particularly as we age we need to keep E within range and just because we aren't getting gyno symptoms or bloat doesn't mean that our E isn't way out of range, and this will affect libido for alot of guys, I'm one of them, 5-10 years ago not so much. At 37 years old both too much or too little E will have an effect on libido. To the OP, just get bloods bro, this is the kind of thing that is so individual there's no way any of us can definitively say what's going on. Most guys report having the strongest libido when E is in the mid to high 20's and Test is in the high-normal range. GIven your situation I would do the following:
1) drop the AI and Mast and keep T at 750, in about 20 days get bloods. That will give enough time for the esters to release the T and most of it that is going to Aromitize to do so, maybe 30 days depending on ester(If it's a really long ester)
2)At 20 days add in your 12.5mgs Exemestane EOD in 10-15 days get bloods again... Now how do you feel? Where is your E2? Libido?
3) I suspect, although everyone is different, but unless your running prop, already really lean and don't aromatize easily that your E will still be 30+. If your libido is fine, then Ok, if it's still not quite up to speed, or if E is 40+ either increase your Exemestane slightly, or add in your Mast. Give it another couple weeks, get bloods.
I would continue to work in this direction until you find yoour sweet spot. I had the same problem, no bloat, no gyno, but very low libido, it's a bit of a pain the first time, but chart your results and learn how much exemestane or whatever your AI of choice is you need at whatever dose of T your running and use that ester so your results are consistent. These days I know exactly how much arimidex I need at 350, 700, and 1050mgs/ week of test and structure my cycles accordingly for the most part...it has really made a big difference libido wise, and I used to never "need" AI's. Good luck.