HCG HELP

So I found out I was pregnant with a very faint FRER test. I went to the doctor and her test was negative so she ordered a Beta HCG blood test, my results came back at 20 yesterday. I would be 3w5d today, I am not due for my period for 4 more days. She said that was pretty low so she ordered another test. I know FRER can detect up to 6.3 mIU so I took a Clearblue Easy Test, which says the threshold is 25 mIU & it was positive. Does that mean my levels are going up if my blood test said 20 but I got a positive Clearblue? I’m paranoid.