Watermelon for breakfast lunch and dinner?

i've been on a diet for about 2 weeks now and was just wondering if eating watermelon for 3 meals was bad? im only eating half of a watermelon total, i think watermelon keeps me full, rly delicious and is also low in calories so i thought it might be a good idea, i dont know much about nutritions and stuff so was just wondering if there could be any health issues or anything bad that can come from this? thx alot lol