I may be pregnant but can’t tell for sure yet

So I am currently 17 years old, and will be 18 in October, and graduating high school in 2019. About 3 weeks ago I had hooked up with a guy, and he used a condom at the end and came into it, and we were doing it in a jacuzzi. We didn’t use one in the beginning, (I know a big no-no) but I hadn’t hooked up with anyone in about a year and was REALLY craving intimacy and made that decision. And starting this week I have been very nauseous, having more mood swings that I usually do, cramps a lot more often, and as of this past hour, my breasts have gotten larger, and I feel tenderness and a different indescribable feeling in them. My period is scheduled to be in about 4 days, and I don’t know if I should take a pregnancy test right now, or do it in a couple days after my projected period schedule. And if I am pregnant, what I should do, as concern of if I should the guy that I got pregnant, or if I shouldn’t and just silently abort as soon as possible.