A little over 3 weeks ago I had unprotected sex (no contraceptive & no condom). 6 days later I felt really run down, I wasn't hungry and didn't eat, and my usual coffee tasted gross, i had a funny taste in my mouth, when ever I was merely sitting doing nothing my heart would race, this lasted for 3 days. From then on I still felt very strange, and 4 days later I had what I thought was 'morning sickness'. I got up for my morning run, and while I was brushing my teeth a wave of nausea came over me and I dry reached. After this, i took 2 pregnancy tests whoch came back negative. 4 days ago (6 days after the nausea) I got what I thought was my period, however it was twice as light as usual and only lasted 2 days. I didn't bleed on the third day. On the fourth day, it was normal flow, but i had severe cramps and I lost a large clot (about an inch long and cm wide)! I now realise the cramps were caused by my body removing the clot. And today I have been bleeding as normal. In addition to all this craziness, I have had a lot of pimples the last 2 weeks, around my chin and on my back, which is insane because even through puberty I never had acne. So my question is this: what is my body doing? Are my hormones just going crazy, or could I be pregnant?