I'm very confused about my (possible) period?

Hi all,
I was hoping someone (anyone really) could give me some advice. 
So I've been in Japan for nearly three weeks now (I'm heading back home to Australia next Saturday) and just before I came here, I had just finished my period which was lucky timing. But then about a week into my trip, I experienced a couple of days of really dark bleeding. I'm talking very dark brown stains and had what looked like a uterus lining shedding. 
It cleared up so I thought all was ok. But then earlier on today when I woke up and went to the bathroom a very similar thing happened and I had been bleeding a very dark shad of blood. 
I went to the bathroom about 10 minutes ago and a huge clump of something came out when I wiped. 
I'm kind of worried... I know it could possibly be an early period but usually my periods are never that dark in colour 
Could it be something else? 😕
Any advice someone has would be great!