oh your chance of miscarriage once you are far enough to get a positive is far under 50% your friend is quite pessimistic.
Feel free to get your hopes up, but know there is still that somewhat increased risk (something like 12-15%, FAR under 50%)
Feel free to tell the world, but know that it may be difficult if something were to happen, or it may help. It's all a personal choice.
So no, not too early at all!
And for your question about your symptoms... they will come and go all pregnancy. Sometimes suddenly, sometimes gradually. You could feel fine and wake up one day with morning sickness, have it for a week and then wake up one day just fine (and be one of the lucky ones to only have a bit)
If you get cramps, that's fine. As long as they aren't severe. Cramps that feel like your period is coming are pretty normal this early in pregnancy, you really only have to worry if they get worryingly bad or you start to bleed.
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