Hello, About A Month Ago My Eyes Became Extremely Blood

Hello, About a month ago my eyes became extremely blood shot, my eye lids were swallon and I had a little bit of discharge in the corners of my eyes when I woke up. I went to the Dr and he put me on some eye drops, I used them and saw improvements almost right away... I continued to use these for almost 4 weeks and I was told I could only use them short term so I stopped.
I wore contact lenses again after 4 weeks, then I woke up with my red weeping eyes again... then they got better, then I wore contacts (to play sport) again yesterday, and they are back red, swallon and a little sore.
What could this be please?