How long does it take for levels to stabilize after a dose change?

I have an official prescription but I've been taking more than I'm prescribed for a while now (90mg). I decided recently I'm gonna try to get my dose upped officially because I want to know what my levels are without my doctor getting sus of me lol. I took my first 50mg dose last week, and I'll take my second today. Could I get my levels tested next Sunday (trough) & have them be accurate for 50mg, or will they still be higher due to my previous 90mg dosing? Should I give it another week?