Mojo and the Mess

Why It’s So Hard to Tell What’s Causing What

Living with cancer means learning a new kind of vigilance. Not just paying attention to your body, but constantly trying to interpret it.

Every ache, headache, wave of nausea, or bone-deep exhaustion comes with a quiet question attached. Is this the cancer? Is this the medication? Is this something I should be worried about, or something I’m expected to push through?

Most days, there isn’t a clear answer. There’s just your body, doing its best inside a system that rarely offers certainty.

Cancer doesn’t stay contained, and neither does treatment. Over time, disease and medication begin to blur together, affecting the same systems at the same time — nerves, hormones, bones, sleep, cognition. On paper, these things are listed separately. In real life, they show up all at once.

Fatigue is a good example. Not the kind that goes away with rest, but the kind that settles into your bones and makes even small decisions feel heavy. Is it progression? Is it treatment toxicity? Is it months or years of cumulative strain? Usually, it’s a combination, and knowing that doesn’t make it any easier to live with.

Pain is the same way. Bone pain, joint pain, nerve pain — pain that makes you pause before standing up or turning over in bed. It might be cancer. It might be treatment. It might be both, overlapping in the same space, impossible to separate.

Headaches carry their own weight when cancer is involved. A headache is never just a headache anymore. It’s a moment of calculation, a flicker of fear, a decision about whether to speak up or wait it out.

Brain fog, too. Forgetting words mid-sentence. Losing focus. Feeling slower than you used to be. Even when you’re told it’s common or expected, it’s unsettling. Especially when your brain has already been through more than it should have had to endure.

There was a morning I woke up with a headache that felt different. Not dramatic. Not alarming. Just off enough that I noticed it immediately. I sat on the edge of the bed, running through the checklist in my head before my feet even hit the floor.

Did I sleep wrong? Was this a migraine? Was it treatment? Or was it something I shouldn’t ignore?

I didn’t message my care team right away. Not because it didn’t matter, but because I didn’t know how to explain it. I was tired of starting sentences with “I’m not sure if this is anything…” Tired of feeling like I needed proof before I was allowed to be concerned about my own body.

So I waited.

By the afternoon, the headache dulled just enough to make me doubt myself. By the next day, it was gone. No answers. No explanations. Just relief that nothing urgent had happened, mixed with frustration that I still didn’t know what it was.

That’s the part people don’t talk about. The symptoms that don’t escalate into emergencies and don’t resolve with clarity. They pass through quietly, leaving behind more uncertainty than before.

Living in that uncertainty is exhausting. Every symptom becomes a decision. Do I speak up or stay quiet? Advocate or wait? Trust my instincts or second-guess them? Over time, that mental load becomes its own kind of fatigue.

Sometimes even doctors can’t offer clear answers. Oncology isn’t linear. Symptoms often come from a combination of disease activity, medication side effects, long-term treatment damage, and a nervous system that’s been on high alert for too long. Not knowing the exact cause doesn’t mean symptoms aren’t real. It means the body is responding to more than one stressor at once.

I’ve learned to stop asking “What’s causing this?” and start asking different questions instead. Is this new? Is it getting worse? Is it interfering with my ability to function? Does it line up with treatment cycles or scans? Those answers matter, even when the cause stays unclear.

If you’re living in the overlap between cancer symptoms and medication side effects, you’re not doing it wrong. You’re navigating a medical gray area that asks patients to carry responsibility without clarity and strength without rest.

You don’t need a perfect explanation for your experience to be valid. Sometimes the overlap itself is the diagnosis.

🐾 Mojo’s Note

I don’t know what hurts or why.

I just know when you need me closer — and I don’t leave.

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