Yeah, yeah, I know it's been done before. That said, I did "come up with it myself" in that I went through the entire thought process of "What's blue? The TARDIS! What's red? ....oh, fezzes! Let's do this."
So I spent 2 hours this morning making this in photoshop and then, lo and behold, there's a valentine's exchange! Perfect.
 I made a higher res version of this for someone on r/doctorwho who wanted to get it printed. If anyone else is interested, let me know!
[another edit] My gosh. Everyone, thank you so much for the wonderful faves and comments. It really means a lot to know how many people appreciate this!
I hope everyone had a good Valentine's Day!