What Causes Bleeding From The Anus?

I am 52 and have had this bleeding from the anus going 4 yrs. I notice the bleeding anytime I eat any food with sugar e.g a cup of tea with as little as 1 cube of sugar, or even fruits like orange, pineapple, grapes, apples. All of which I love a great deal but have had to stop. Surprisingly I tolerate water melon, pear. The bleeding can be much and when I clean with toilet tissue I often see something that looks like tissue or some clot I am not sure what it is. I also notice my anus is swollen with 2 extended soft tissue around it which bursts and the blood increases. Even when not straining I can hear the blood dripping. I have read a lot about rectal needing but I am scared if the description of the type of examination to be done. Sticking pipes and tubes up my back side. Pls help explain what this may be to enable me prepare myself fir the examination.