Confused

Ok so I’ve ALWAYS started my period on the 2nd of every month. Literally the only 3 times I haven’t. I’ve been pregnant.

I had a miscarriage a year ago on February 14th I I was 10 weeks) I have 2 beautiful daughter’s (10 and 5) I’ll be 34 this month.

Ok so my boyfriend and I had sex May 9th. And I’ve taken 6 tests all negative. I’ve tried to track my fertility week on 2 different apps. One says I could be 6 weeks. Another says 3 weeks. It’s June 5th and I still have not started my period yet.

Some light spotting (like if I wipe hard some blood but that’s it and not every time)

My back has been KILLING me since about the 30th. (I don’t get cramps I get major back aches) which is about eh same time as every month my back starts hurting a day before my period starts..

I’m so confused and I just want to know. My best friend is having her bachelorette party this weekend we are supposed to float the river. I told her if I’m pregnant I will not go on the float trip. I just won’t take the chance- I’m super terrified of having another miscarriage and don’t want to look back and wonder if being in the sun all day, on a dirty river caused it.

I don’t know if I should just wait it out til I start and not go on the float trip/ not drink just Incase..

Or what..