While i agree with Krab 1 about it being a too late to learn anything, i'm going to post a list of some ideas anyways, because 1, someone else will ask, and 2 maybe next year people will USE THE SEARCH button and just find this.
1) A rose production is always nice. My personal favorite is David Stones from his dvds.
2)Anniversary Waltz effect (really any version) is always a huge hit with couples. If you don't know this is an effect where two spectators sign the Back of two separate cards. The cards then "fuse" and become one, with a single card that has two signed backs and no faces.
3) Psychokinetic touches can be very powerful in giving the impression of a connection between two people. David Blaine demonstrated that very concept in his latest special.
4) I forget the name, it might be "Kissed" but it is a magic card trick with a production of a hershey kiss. Another great trick for the romantic touch.
5) Wayne Houchin's "French Kiss" is a great effect. It can even be adjusted to fit two spectators rather than you and one spectator.
6) Pretty much ANYTHING with a woman's ring. Apollo's effect with the Gaeton Bloom ring fight is my personal go-to ring effect.
7) Gypsy Thread can be routined to be a nice story about love and connection.
For more inspiration check out Patrick Kun's youtube channel. He has done 2 great valentines day magic videos. Remember, the effect is less important than the story behind it. You can routine just about anything to be related to Valentines day or love or whatever. Just think about it. Whatever you do, don't try and force out a magical moment in 72 hours. If you haven't put in the time to do this blindfolded than simply focus on making the day special in some other way. Magicians don't have to "magic" every aspect of their lives. Sometimes a nice dinner out during which you DON'T EVEN BRING YOUR CARDS can mean the world to someone. (i know from experience). Good luck and many happy memories to everyone and their loved ones. Happy Valentines Day theory 11!