Nellie Please don't feel guilty for sometimes feeling down about your health, we all do from time to time and even though we know others have it worse, we are still entitled to feel rubbish at times. The difference is to dwell on it as we can't alter it and if we can, then we must do all we can to do that. We must look after ourselves and listen to our bodies, I think so anyway. It's fine doctors saying this and that but I have lived in my body for 50 years now and know it better than anyone. It is only a system. Learn about it and get some knowledge as knowledge is power. I have lost some faith in doctors as they just throw prescriptions at you and let you go off and have another month taking the pills. As long as you don't rattle too many cages then all is fine. So I find things out for myself and then go and rattle some cages.
You be how you want to be, I worry from time to time too but then think I've had 50 years so try to look forward to my next stage of my life, having lots of sex with husband no. 2, lol. Well, that's what my mind thinks sometimes, inbetween adverts on Corrie. 
Keep your chin up love, keep smiling and put some comedy on youtube, have a laugh. Tele can be miserable sometimes so this is what I do, it's important to laugh. X