That's a really honest reflection, and I think a lot of people in similar situations have asked themselves the same thing. It's natural to look for an explanation when things feel harder than expected.
Something worth considering is how much of the struggle comes from the early stages of building new workflows. The first few months of juggling two roles are often the toughest, regardless of cognitive ability, simply because systems haven't been set up yet and everything requires conscious effort. Maybe it's not about whether the workload is realistic at all, but about how much time is available to adapt and create shortcuts that make the routine more automatic.
There's also the question of whether traditional IQ tests actually measure the skills that matter most in this particular context. Areas like task switching, focus management, and building efficient routines might not show up in a standard test score, but they play a huge role in how sustainable this setup becomes over time.