As ingi said, you have to take your pill every day at roughly the same time. Keep in mind that it is a 24 hour pill, not a "when you feel like it" pill. being even 12 hours late with your pill (not even one full day!) can increase your chance of getting pregnant. Stuff like that really needs to be done right or not at all. If you having that much trouble remembering to take the pill, try some sort of schedule or alarm clock as ingi suggested. If that does not work, you could either always use condoms or talk to your doctor about other options that you don't have to worry about every day.

As for the std part, I am going to echo ingi again. Not all stds have symptoms, so the fact that boyfriend does not show signs of any, sadly means diddly. Hiv/aids, the most deadly of the stds, often gives the infected person no symptoms at all. There are other stds with no symptoms too. Some of them, if left untreated, can cause other problems.