It'd be a bit unreasonable (at least in my opinion) to fully critique both pictures, since as the title says, they are both doodles. So I will primarily focus on what I like about them both.
For starters, I must say, there's something about your ability to draw in different styles that greatly fascinates me. I feel that enables each of your drawings to have their own unique identity, which makes them stand out from one another significantly.
I can sense this while looking at both doodles here. They each express one or more distinct emotions, with the strongest one being the first doodle; the monochrome character's mouthless expression and silent observation of the mirror conveys plenty of feelings that I feel would be left up to the viewer's interpretation - the fact that its a Valentines doodle really strengthens this aspect.
As for the second doodle, I like the anthro-cat angel's pose and expressions, as they go hand-in-hand with each other. I can't say a whole lot about the disembodied head beside them, aside from how beautiful it looks, and that it also appears to be a practice sketch for a more realistic artstyle.