Help I need advice

You guys I am exhausted. My boyfriend just had a bowel obstruction and I had to take him to the ER, I checked him in and wasn’t able to stay so I dropped him off.

I work in a cancer unit & it is intense, stressful, and so fucking busy. I love my job though and bust my ass everyday! Recently we have gotten an overflow of patients due to a local cancer center closing down. It’s caused us to be busier. I am drained and exhausted, massive headache and need rest. I’ve been waking up aching and so tired and sore . At the end of my shift today my eyes were so sore and hurting! I finally have no patients tomorrow and I am really wanting to call in. Im not sick (flue/Covid etc)just exhausted and I don’t feel like lying and saying I’m sick, I was wondering if it’s okay to say I am hurting and exhausted and have a headache and don’t feel physically/mentally good enough to come in. Is that okay to say? I never call out and I’m a really good worker and dependable but I just need a mental day and I don’t know how to admit that! Being surrounded and busy with cancer everyday just takes an emotional mental toll on you ya know. Thanks guys.