Hmmm... difficult question. I think it depends. There's two ways of getting horny for me, both rather different. And it's not always black/white either, there's a grey area.
When I'm ovulating, and my hormones are basically trying to get me pregnant
Then it's a more needy, humping pillows, I neeeed to orgasm horny. Definitely in spring/summer that can be pretty strong. There just seems to be a constant bigger bloodflow to the whole vagina/pussylips area. I'm much more sensitive. Wearing a skirt and feeling a breeze at the wrong time can get me distracted from whatever it is I'm doing at that time. Even if I'm wearing a jeans during those days a breeze can give me goosebumps all over just because I'm more sensitive. And sometimes I catch myself of wiggling against the seam of the jeans when I'm alone. Luckily, I don't do that completely unconsciously, I catch myself in time when I'm doing it when there's people around. But I'm generally distracted much easier by naughty thoughts.
And then there's the horniness that comes from getting my brain played with. That can be anything. A romantic moment in a good movie that makes me go awww and that I feel in "the pit of my stomach". It's like an involuntary tightening of my pc muscles or uterus or both (I can't really explain), it makes my breath hitch.
Seeing a hot guy on the street without a shirt on. Having someone whisper in my ear. Even just eyecontact can cause this.
After a long romantic movie I just feel all warm and cuddly and I want to be somewhere really comfortable and just... hug myself? It's a more full-body experience? I get in this state of mind of comfiness and coziness and warm and pleasant feelings and my whole body gets tingly and I get turned on.
The end effect is the same, but it feels like a different kind of horniness. Less needy. It's just fun to be in that state. I don't mind at all if I stay like that a few hours.
When I'm hormone-induced horny, I just want to orgasm. And as soon as possible too. When I did, I'm done and can get sleep or go on with whatever it is I was doing.
I did notice a BIG change after I went of the pill. I was much less aware of this "difference" when I was on it.
Does this all make any sense to the other ladies or am I alone in this?