Endometrium still thick after period and corpus luteum big

So my period came 10 days early and it was extremely light however, I did have some small clots. Anyway, I was having some pain and went to the Er where they did a pelvic ultrasound. They said I had a UTI and told me I was about to start my period 🤔. Anyway, upon looking at my report, I have a large corpus luteum cyst on my right ovary and my endometrium is 7mm so I’m sooo confused. After they gave me fluids and stuff, the bleeding was COMPLETELY gone. The light bleeding last 3 days with no real flow. My tubes are tied just to add that on.