I think you are just researching things of interest/concern to you. I remember reading a lot of counselling books when I was in therapy, just to compare how my therapist did therapy against what the books said? It's a natural thing to want to do. However, if you spend a lot of time doing it and going to doctors, etc. and don't want to spend so much time doing that, then see if you can find "different" interests? I'm interested in weight loss but tend to study food history and nutrition, for example. That way I don't fall into diet traps or other oddball "cures".

If you worry about a particular illness, why not experiment with detecting it better or helping it by doing things someone with the illness probably wouldn't do? If you think you are depressed, think of something useful/concrete to do and then immediately go do it, for example. Start eating better and setting a regular time to go to bed and get up and see if you can follow your ideas for a week.