Okay I Had Sex On August 5th, 2015. My Boyfriend

Okay I had sex on August 5th, 2015. My boyfriend and I, we used protection. It was my first time having sex, the thing is, is that when we were having sex, I was really wet, but it was a lot of liquid, but I don't know if part of that was because some of his cum slipped from the top. That was a large amount of liquid on my body but I'm not sure if it was just me. 3 days after having sex I started to feel nauseous and having little stomach aches and having to poop, but not the solid kind. Then earlier today around 4:35 am I kept having temperature changes like 1 minute I'm hot and the next I'm cold. And I haven't been able to sleep, no specific reason but I stay up till like 5am at the latest then fall asleep later. Is it possible I could be having pregnancy symptoms after 3 days of intercourse? Is there any way to tell that I'm pregnant within the first week of intercourse? If you could write back with all details and more clarification on my misunderstandings that would be greatly appreciated. Please and Thank you.