Need help with negotiating rate

I think payment will still be through upwork. They paid me today, almost 2 weeks after submitting, and it now says no active milestones 0 in escrow 0 remaining. Like I said I am new to this, so I'm asking what I need to look out for to not get screwed. The only agreements have been through messaging, and I only signed an NDA. I shouldn't have said a bunch of stuff, it was just the one NDA document that didn't mention a contract. The only contract was through upwork- it was $40 for the one task.

What I thought I was agreeing to was doing more of the same for the same price which came out to a reasonable wage, pre taxes anyway. The only time 0.04/w came up was after they already sent me the batch to work on. As far as upwork, I am out of connects and wasn't planning on buying more anyway, so if they boot me... shrug.

/r/freelanceWriters Thread Parent