Is it normal to have such a strange period

This month has been really weird. Normally I start a day or two later then glow predicts, and occasionally right on time. I also usually have brown spotting the day before or just hours before I start, I’m very heavy the first day or two, and I usually have horrible, horrible cramps. My periods usually last 5-6 days. According to glow, I was due to start the 18th or 19th.

I started spotting on the 13th, that lasted until the 20th.

The 13th-15th it was very, very little brown with pink.

The 16th-18th it was just a lot of brown, gooey discharge.

The 19th I had some brighter red then usual, slightly heavier then the spotting (but not as heavy as my usual) with some brown in the morning and I though “oh okay! Now I’m finally starting” but then the rest of the day it was only brown spotting. Same thing happened on the 20th.

Throughout the whole time I was spotting, I had absolutely no cramps. Since it has stopped, I have had on and off, slight vaginal cramps, backache and head ache. I’ve tested every day since the spotting stopped and all have been negative. Is it normal to have a period that far from my normal?