He suspects something is amiss when she gets home before he does.
Martha Kent didn't exactly raise a fool and Clark doesn't think himself especially stupid when it comes to Lois Lane-Kent. She can be pretty transparent - okay so, to him, transparent has a few meanings. Nevertheless, he's more than a little suspicious and it doesn't help that when he reaches the entryway, he catches the faint scent of something burning. Superman claws at him, wanting out, wanting to assess and analyze all possible causes but he resists, keeps his superpowered alter-ego at bay.
"Lois?" the second set of double doors isn't locked - which, he grumbled vaguely about one night when trouble lurked in the shadowed corners of Metropolis - and he enters the house with a little bit of fiery panic scorching his stomach. "Lois Lane Kent? Lois!"
Nothing.
Not even a laugh at his frustration (read: panic).
But, his super-hearing hears it before his brain can register exactly what it is. Crying. Sobbing, actually. And, it appears the be coming from the kitchen. Already fearing the worst, Clark's briefcase hits the floor with a thump and he's sprinting into the kitchen, red cape billowing behind him before he even realized he'd slipped into his alter-ego.
"Lois? Honey?" a quick glance around the kitchen reveals the culprit, smoking on the stove, but that can wait. "Lois?"
"Clark?"
She's curled up in a ball in one corner, dark hair clumped against her damp cheeks, and her soft eyes slightly swollen and very red. No injuries detected. He sinks back into Clark and makes his way to his crying wife.
"Hey," he kneels down before her. "You wanna tell me what happened?"
Lois just shakes her head, mumbles something about how he'll laugh at her. "I don't want you to laugh."
"I'm a little worried, right now, Lois." Clark reaches for her hand. "I couldn't laugh if I wanted too. Now, please tell me why my wife is crying in a corner and my house smells like smoke?"
"Today's February twenty-eighth."
"What?"
"February twenty-eighth." Lois flails a little, "It's the closest to your birthday I can get so I thought maybe I could bake you a cake."
"Lois, you - you can't cook." but, he doesn't laugh. He might rib her a little bit, later, but now's not the time to laugh.
"No kidding." she crosses her arms. "I kind of burned it."
"Sweetheart," it takes a bit of rearranging but he manages to get her out of the corner, wiggle himself into it, and take her into his lap. "I don't need a cake. You don't have to bake me, anything."
"But - "
"You're my wife, Lois." Clark brushes a clump of dark hair from her cheek. "I got all I need when I married you."
"Why did you marry me, anyway?" Lois pouts. "I can't cook."
"Well, I'm not an idiot." he chuckles, leaning forward a little kiss her head. "That doesn't matter to me, Lois. What matters is you. Today is just a date. You are more important and you have no idea what went through my head when I walked in and smelled smoke. I thought something happened."
"I'm sorry." she sinks a little further into her husband's warmth.
"Don't apologize." with a tender smile, he brushes a thumb under her eye, wicking away the tears still gathered in her eyelashes. "Feeling better?"
"I guess." truth is - she still feels like crap for not being able to make her husband a cake. Even a simple one out of a box. She wants to be able to do sweet things for her husband - return the favors, once in awhile.
"Can I look at it?"
"No!"
Clark just laughs and braces her against his chest as he stands up from the tight corner. "Well, how about I take you upstairs, run a bath, and I'll order us some dinner while you relax?"
"You spoil me." Lois smiles, nuzzling into the collar of his shirt.
"I love you." his arms tighten around her. "Even if you can't bake a cake. Was it out of a box?"
"Shut up!"