I am new to gardening (just started last summer) and Dahlias. I have a smallish variety 3' tall and 3-4" flowers and had my first flower open up earlier this week. Yea! Petals are falling off the flower already, is this normal? I think the flower has only been fully open about 5 days maximum. Does this indicate a problem of any kind? Last week was 95-100 for the entire week so perhaps this is a sign of stress?

Many thanks in advance for your feedback.