Good Morning lcg842!
I'm hearing a great deal of stress from this post but I'm having a difficult time trying to decipher what your major concern is. Is it STDs, specifically the Human Papiloma Virus (since you're mentioning your negative Pap tests) or pregnancy?
Let's address the pregnancy first. If you're on the pill and taking it regularly, it's not terribly likely you could have gotten pregnant.
As for HPV, there's always some risk because most people who have don't know it. However, it's impossible to know if either of the partners you mentioned have it. By the information you're giving, it does sound like the chances are high they DON'T have others STDs.
It might be a good idea to monitor your stress levels first. If you're intensely worried about these sexual encounters, perhaps talking to a counselor or your doctor could help. The next best thing you can do is have a yearly Pap (like you're doing) and continue using protection like you've been doing.
Take care,
Dharma