Hey. Yes you can use just one website to promote multiple affiliate programs, but I’d say that your website should focus on just one niche. So you mention, SellHealth, that would lead me to believe your site is about health and fitness. I would then advise you to stick to that niche rather than promoting unrelated products like dog leashes and fashion accessories.
I concluded that having read a product review, people felt more informed to make a purchasing decision. As a result, if they did click a link after reading the review they were more likely to buy the product. Those clicking on the top link seemed to be more in a ‘surfing’ mode. They clicked on the link less because they wanted to buy it but more out of interest to learn more. Some bought the product and some bought other products once they were ‘in the door’ at Amazon.