Appropriate Statistical Test to use?

Good day.

Can I ask what's the appropriate statistical test to use if I have 1 IV with 3 levels (no treatment; 5mins treatment; and 20 mins treatment); and 1 DV and I admisnistered the experiment on a between groups.

No treatment - control group (22 people)

5 & 20 mins treatment - Experimental group (19 people) both administered on the same group of participants.

It's like, after the 5 mins treatment I measured the DV then rest and then administered the 20mins treatment and measured the DV again

(given that the 2 measurements for experimental group are 80% the same. While the control group have 100% the same measurement as the 5mins measurement; and 80% the same as the 20mins measurement)

Thank you.
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