First time travelling to Playa del Carmen - staying at Wyndham Alttra (adults only)

Hi everyone. It's our first time travelling to Mexico and actually my first long haul flight, so I am a bit nervous. We'll be travelling there in two weeks and we're staying at Wyndham Alttra for 8 nights. I have some questions and I hope you can provide some insights:

- Does all-inclusive here really mean everything is included (excluding specific restaurants)?

- How is the weather at the moment? Weather forecast shows rain and it's definitely a downer considering that we're travelling from the UK.

- I've read all the warnings about water, food etc. Is there anything else we need to consider?

Thanks!