HELP? Super irregular period out of context

Question for you ladies, since I really don’t know what to make of this.

My period was late this time around. I took a test and it came out negative. On Christmas Day I saw a few drops of blood and then it completely stopped. The next day, the same thing happened. But now, still nothing.

I know I’ve been really stressed lately so I don’t know if that’s messing it up, but also my husband and I just about never use protection because we’ve been trying for the last 2-3 years.

Has this ever happened to you? What were the circumstances surrounding it? At what point do I need to go get checked out?