Erectile issue

Patient: Dear Sir or Madam,i am a 32 year old male 6’4 90 kg and healthy, my question may seem a little strange but i dont alway seem to get fully erect (ie pointing to the sky) and it kind of droops but is semi hard, could this be due to having a large penis and the weight of it causing it to hang down or do you think i may have a erectile problem,thanksScott