Chances of pregnancy?

On December 3rd. we had unprotected sex. This isn't the first time we had unprotected sex, and I am more than capable of pulling out since I know when I about to orgasm (I am in a way able to hold it back through sheer will-power alone, but only for a few seconds). I was sensitive and so I orgasmed early. The problem was I was originally inside of her, and when i felt my orgasm come along, I pulled out but I'm unsure if it was in time. I had the sensation of blood rushing to my penis, which is somewhat similar to an orgasm, (the rushing feeling) once before i pulled out of her. I let it out on her, and cleaned it off, then put my fingers inside of her to see if I actually had came inside of her. When I pulled out my fingers, I seemed like there was only her juices (completely clear and slightly sticky). This happened a day before her period was supposed to start (supposedly it starts on the 4th or 5th). Calcium can throw her menstrual cycle off and so can the stress since she is in college. We both are worried, but from what I can see, it was a day or days before her period so what might be the chances of her being pregnant. Yes I understand that semen can live inside the uterus and vagina for a period of time, most commonly 5 days, and we had sex from Nov. 23rd to Nov. 26, several times a day. During that time, I made sure to ejaculate outside of her, clean the tip of my penis before we decided to have sex again, and went to the bathroom to flush out any remaining semen inside me. I'm just worried since we accidently got into the bad habit of unprotected sex. We discussed this and now we're planing on protected sex only. 

What are the chances she is pregnant, may become pregnant this month, and may become pregnant the following month?

She started her last period on Nov. 4. We had sex on Nov. 5th, 23rd - 26th, and again on Dec. 3. She has a 30 day cycle (usually). Too much calcium can throw off her cycle and so can stress due to the fact that she is a college student. 

Thank you for you time.