End of period and had weight gain???

I got my period on Aug 28 and it lasted exactly 5 days which is weird because my periods normally last longer and it does not always fall on the same date each month. Towards the last 3 days of my period I noticed the extra weight gain, bloating and it felt like I was getting my period again? I normally get all the symptoms prior to my period and it ceases towards the last few days but this time even before it (period) finished I was getting the symptoms. The last 15 days have been up and down for me...i.e restless, cannot sleep, gone off certain foods, lower back pain which I dont get, cramping for 2 days, some food cravings, breasts bit tender, slightly dizzy and nauseaus. I will also take a pregnancy test in the next 2 weeks but if anyone can shed some light on their experiences that will be great!!!!! Cheers :-D