Thanks a lot for your creative and spot-on interpretations! These are indeed two (mannequin) heads. The red dot at the bottom is the last glowing heat from a burning wick. The item is therefore the upper part of a regular candle. Of course some incense device would work as well though. I tried to evoke the shape of smoke rising from the extinguished candle (there is some real smoke in there as well).
I love the bolded statement above by @minniev with 'the point' being, that I view the title as a well-trotten cliche. People say things like that and often mean the first stage of being in love, which is far from the only one. Therefore I also really enjoy what @MikeFewster mentioned (also bolded): '...love can grow as well.' Indeed, I believe it can change and grow and shift its shape over time and perhaps we shouldn't focus on the (inevitable) fading of the first stage, the 'falling in love' (the right mannequin head actually is upside down...) as something negative.
Thanks again for your feedback!