At your age I do not see anything alarming about the rise of 1.4 in a year, even though most of it was within the last three months. Your PSA can fluctuate naturally by that much. I really like the fact that your biopsy came up negative last year.
Have you had a Free PSA done? If not I would ask your Urologist to order this blood test as well because it can give you some more info to go by. Has your Urologist ruled out BPH?
If you have already gone through a a course of antibiotics for BPH then I would assume that if your Free PSA comes back abnormal, your Urologist will probably suggest another biopsy.
Good luck and keep in touch!