Photo would be good, but what do you mean by "watering regularly" precisely? If you mean you're giving the plant a drop of water every day, don't. When you repotted, what compost did you use? Was it potbound initially in its old pot and did you tease out the roots? And did you thoroughly soak the whole thing, so that water poured out the bottom, when you finished repotting?

Watering every day using a watering can - is that too much? It just looks so dry. My dad repotted for me and he is an experienced gardener so I presume he did tease out the roots. It was just regular bought compost and we did thoroughly soak it after we had repotted. We repotted because it had fallen over and the pot had broken plus the pot looked a bit small. Thanks.

Sounds like the process of repotting was done properly then, plus watering at the time. No, it's not the right thing to water every day, really, it's always best to thoroughly soak a pot or container and then let the compost dry out a bit between waterings. This assumes there's drainage in the pot, that you've soaked it sufficiently for the water to run out the bottom, and that the pot is big enough for the plant. That said, small pots in hot sunshine will need watering daily, though.
Only other possibility is damage to the plant and its roots when the previous pot got broken - when did that happen and how long before you noticed?
And welcome to GoY by the way!