Is my tank cycled?

[AbbieM]

I've been cycling my 330litre for about 3 weeks with fish food. I saw a slight ammonia spike for a couple of days in week one and nothing since then. I didn't test the nitrite until about a week ago because I was pretty sure it was to early. The reading was 0. It's been another week and I've been adding fish food every day and testing for ammonia the next morning. The highest it's gotten is 0.25ppm. Today I decided to test the nitrate because I was wondering if it was already cycled because I used some gravel from my already established tank when setting it up. The nitrate reading was 5ppm. Is it possible that it's cycled already? (Both the nitrite and ammonia were 0ppm this morning)

 

[DutchMuch]

I would wait a few more days and test every day within those few days (so many days) just to make sure, but sounds good to me just do this to double check.