Did something go wrong over sandwiches?

Scott Disick and Sofia Richie grabbed lunch at Marmalade Cafe in Calabasas on Sunday, and we couldn't help but notice how pissed the teen model looked as they made their way out of the restaurant. We have a feeling they had fight over their meal. Yikes!

Their romance has been going smoothly for almost two years now, but every couple gets into spats every now and then.

A source tells X17:
    "Sofia is madly in love with Scott, and sometimes she gets insecure that he's never going to make things official and propose. While she's still young, she knows she wants to marry him, and she can't help but feel that he may never be ready for that. She's trying to play it cool because she doesn't want to push him away, but it gets to her sometimes."

The Lord has major concerns, though, given that he already has three children with ex Kourtney Kardashian.

Another insider told us:
    "Scott knows that marriage means starting a family and having kids, and he doesn't really want any more. He has a hard enough time juggling three kids with this relationship, and he's not the most stable person to begin with. Whenever he has too much on his plate he spins out and starts drinking and partying, so he's not trying to rock the boat."

Sometimes it's best to fall in love with someone without so much baggage!