I used the hot tub at 18 weeks. Just pay attention to your body, you'll know your limit.
Do you mean hot tub like a spar? Never knew it was an issue, I went in one twice on my honeymoon when I was 23 weeks :) nothing happened and I'm now 30 weeks
No because it can raise your temperature which is dangerous for your baby.
No you can not it will put u in to premature labor