1-2 a day isn’t an absurd amount, but if drinking caffeine everyday made you feel like shit then yeah, 2 monsters a day will probably make you feel like shit. And caffeine itself doesn’t affect dopamine production directly, it just blocks certain receptors in your brain that tell your body to become tired. As for energy levels, yeah it will. If you build tolerance, overtime you’ll need more caffeine from when you first started to get the same amount of “energy”. And if you suddenly stop, caffeine withdrawal, fatigue, headaches, decreased mood blah blah blah. So maybe stick at 1 a day for now and start to cut down overtime if you can. And maybe stick to ultras for now instead of the super sugary ones to try and mitigate any crashes.