I have not taken a test yet but I there is a posibility I am 3-4 weeks pregnant. I noticed a ligth pink discharge last night, and this morning I was bleeding heavier than I was and still am. Is it possible that I am having a miscarriage?

It's possible, or it's possible that you are having an "off" period. When in doubt... test.

I'm sorry I forgot to put that I had a period that lasted 2 days on the 19th and 20th, and usually my periods last about 6 days. And then this started last night

When in doubt test. Remember to test using first morning urine as it is more accurate.

OK thank you