When you said "Now I have this feeling that people are wondering what this round bellied middle aged man is doing taking a photo of that...." it says to me that this isn't a photography issue. It's a general life issue that's effecting your photography. In other words, it sounds to me like you're lacking in self esteem. So I would start by addressing that. Maybe start an exercise program. Those are great for your self esteem on so many levels. They help you to control your appetite, which combined with the exercise, improves your physical fitness and helps you to lose weight. That improves your body image and gives you more energy. Feeling physically tired can make you mentally tired which can make you depressed. Exercise also helps to regulate your hormones, like testosterone, which can fight depression on a chemical level. Falling testosterone levels as you age usually have a negative effect on your self esteem.
In the short term, buy a photographer's vest. It should change your image of yourself and make you less self conscious. With a photographer's vest on, you'll look more like a photographer hard at work than a "round bellied middle aged man" with a camera, creeping around.
In the short term, buy a photographer's vest. It should change your image of yourself and make you less self conscious. With a photographer's vest on, you'll look more like a photographer hard at work than a "round bellied middle aged man" with a camera, creeping around.