Yeah, anything is possible with bitcoin as you never know what is the future of bitcoin, its better if we invest our money into multiple products.
I don't think investing in multiple products could be a wise move as any other product is more dangourous then bitcoin for investing, but also as a mate said above putting all the eggs in one basket is not good so better to invest a half in bitcoin if you believe it and do something else with the other half. The half invested in bitcoin won't make you regret your decision for sure.
yes. but choose bitcoin investment source wisely. there are thousands of scam/ponzi investment sites who ask people for invest their money and promise them to give them double after some time. but all of them only bullshit. so if you want to invest in bitcoin then you should search about investment source properly before investing.