Over the past 2 or 3 weeks, several different things have happened that don't normally, and I'm wondering if they could be related, if they could be serious, etc.

I don't usually freak out over random symptoms, but these worry me a bit.

The first was that my period was a week or so late, but I figured that since I stopped using birth control within 2 or 3 months of this, that it probably made me slightly irregular.
But then, when it came, it lasted all of a day, maybe.
Normally, they last 7-8 days or longer, and are heavy.

The second was seeing light, or shadows flitting across my peripheral vision.
My family said that it was probably related to sugar intake, so I've cut out sugar intake, to try and help.

The third is swollen ankles/calves.
From the knees down were swollen from what I guessed was water retension, and painfully swollen on the feet. They didn't hurt to just sit normally, but to touch or bend my toes/feet was, and is, painful.

The fourth, and most recent is rectal bleeding.
The first instance I assumed I was finally starting my period, since I hadn't technically started yet.
But then today, I had to have a bowel movement, and I had to clench my hands because the pain was so searing, and the water AND toilet paper had considerable blood on them. Again, from the rectal area.

So... what do you guys think? Could these symptoms be related in any way?
Could they be something serious, or just attributed to stress, or diet? O_o

Help is much appreciated