Cold Penis Erection problem

Patient: Hi I am 18 years old and over the years my sexual arousal and penis health have declined. Recently my penis has gotten cold and is difficult to stimulate. It has gotten very bad and weak almost spongy especially the upper half. now i find it difficult to get erections although i can stimulate them and orgasm it’s hard. and the mid section is very weak. the bottom half fills up massive and then the upper half reluctanly follows. what do you think this is and what can be done.