Confused if I had periods

Ladies please help! So I normally tend to have periods lasting 10 days ( the last few days is just brown blood) and my usual period colour is deep red. I am supposed to be 4 weeks pregnant and my usual periods tend to be a 25-27 cycle.

Here is what happened:

day 25

No cramps. Cm watery.

day 26

Cm watery. Light spotting. Cramps and back pain but possibly due to the long 8 hour flight

day 27

Cramps. Back pain. No spotting.

day 28

Cramps.

Had sex twice:

Once around 1am before going to bed and noted spotting on toilet paper when when I went to the loo.

Woke up around 9 am, went to the loo, no blood noted. Had sex again once back from the loo and noted bright red bleeding.

Filled up: one pad, 2 tampons in a 12 hour period.

Maxi pad put in place late evening- 1/4 filled in

Very minute clots.

Day 29- bright red blood, filled 1/4 pad. No clots.

Day30- blood now deep red, filled 1 panty liner

Day 31-32- same panty liner used. Not much bleed

Day 33- no bleeding.

I would have gone to the doctor but I put or the UK currently.

I currently have minor lower tummy cramps, and also tend to get cramps in my left pelvis a lot - today they lasted on and off for about two hours.

Anyone know what could be going on????