Santana was waving to Brittany, but Sam was there waving back, too. It wasn't a happy wave, I'd say more awkward but it's subjective and open to interpretation.
Every time Santana says something crappy about Valentine's Day and/or the wedding, they make sure to show she's watching Bram.
Quinn tells Santana she looks good in her dress and touches her arm. Then when they are dancing, she tells Santana she likes slow dancing with a girl.
Santana realizes Quinn is flirting when Quinn brushes her arm after complimenting her dress. But no, that moment and the slow dance talk are it. Besides their bitch fest about weddings after Santana waves at Brittany and Sam.
We Got Tonight plays during the slow dance, then they are shown goofing around down the hall to their room where they sing their lines before going inside.
The after-sex talk is all about experimenting. Quinn says she'll probably never do it again, but sees why college girls do it. Santana says she's grateful for experimenting college girls.
They are shown covered in bed together, but at different ends of the bed and not cuddling or anything.
Quinn asks what's next. Santana gives her the option of a repeat and Quinn takes it (Smiling and putting her water bottle down). They don't show the execution.
Bram interactions: Legs on his lap in the choir room, cuddling in church, having a blast dancing, slow dancing.
Rachel and Finn have sex, Rachel runs off before Finn wakes up.
The shocker is Rachel taking the pregnancy test.