Flirting

Is tickling a sign of flirting?

We were doing P. E. and I was lying on a mattress after a game with my stomach facing the ceiling (I was wearing a tank top and a pair of shorts). Other people were around but I wasn't talking to anyone. I saw my crush coming at me and after giggling a bit with another guy of our class, he acted like he was gonna sit on my stomach but didn't and laughed. I said he could if he wanted and he did. Then I kinda lifted my waist up and he was impressed that I could do that. I said "come on you don't weight that much!" After that, he got up and walked around a few seconds but he was still turning his body towards me. I said he could sit next to me and he did immediately and he started tickling me A LOT. We were both laughing and he was like "so you ARE ticklish!!" and kept doing it and after a bit he held my wrists together and said to our friend "I hold her, you tickle her!!", our friend didn't so he started again giggling a lot and smiling at me.

Is this flirting or could it be just a friendly thing?
Updates
+1 y
I should also add that while tickling me, he was almost with his body on the top of me, he was really close and we both had our hands running on each other. And when he took my wrists in his hands we were facing each other even though he was sitting next to me. But then again, could this be just a friendly thing?
Is tickling a sign of flirting?
Post Opinion