Botox or fillers for horizontal line between eyebrows? (photos)

I'm almost thirty and I lost a lot of weight a few years ago and my face has some loose skin now. it doesn't bother me too much except I have this line between my eyebrows and I think it makes me look angry. I thought it was pimple scars but it creases when I squint too. I was thinking of getting botox for my tension headaches which develop in my forehead and over my eyes but I was wondering if I could also fix that line between my eyebrows as well.