QPCR Contamination Or Evaporation

I was running a QPCR to detect for a fungus with 40 sample in duplicate so 80 wells in total plus standards. The standards amplified as expected and 79 of the wells came back negative as expect however one reacted strongly and was detected well before that strongest standard. It then amplified to half the height (along the Y axis) of the standards then levelled off fast. Was this contamination of the well, evaporation or something else. I’m concerned as evaporation could damage the machine however it did not look like anything

https://ibb.co/j559n5

I have included a link to a poorly drawn diagram of what it looked like.