Are we too strict?

Recently i noticed that P is behaving differently.

Incident 1. She was having her breakfast at the dining table, and i walked to the room to get something. When came out, she had clean up. It was too fast, so i asked if she finished her breaky, she told me yes. But when i checked the rubbish bin, her breaky was there.

Incident 2. She came home with red paint on her sleeves and bag. I asked her what happened, she didnt reply (which is absolutely normal from her, which kinda piss me off). Later she told me her fren spilled paint on her, since her bag had spashed paint, and i suspect most likely is during shower time. After toking to her teacher in the morning, it is her n mayb with her fren playing with the paint n spilled.

I wondered if it because she is worried we going to scold her and she lied/ refused to tell us what happen? I did those when i was younger to avoid being scolded. Are we being to strict to her or are there something wrong with my parenting? I dont want to be in my parents' shadow.

I am at fault too, i m spending less time with P due to work, got super frustrated with her at time. I m afraid things will get worst, when the extended family is coming in 2 weeks time.