Mead equalised for Arsenal just before the end of the first half, but Signe Bruun added another to Marie-Antoinette Katoto's opener.
Arsenal forward Mead told BT Sport: "We played in to their hands quite a lot. Maybe we [showed] a little bit of a lack of experience in this competition.
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"We had quite a few pre-season friendlies and we thought we were in a good place. But today was their day.
"Everyone wants to come over to our league and play there now and now as English teams we want to compete [in Europe]."
Gunners boss Joe Montemurro said: "I've mixed emotions. It's hard to put your finger on one or two things that didn't go well.
"I'm very proud of my team, under difficult circumstances in regards to preparation and so on. But it's the way it goes. There are no excuses and so on."
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