HCG Levels

So I got my HCG Levels taken on the 9th and they were 341. Got them taken again yesterday 14th and they were 2432. I know this is good, but on the 13th I went to the ER for fluid leak, which was just BV, and they said my levels were 2600, after I pestered them cause they wouldn't tell me anything about baby or my bloodwork at first. My question is, is it normal for it to drop like that, or could it be just a variance because of different labs?