Cramps and sudden shooting pains sounds like stretching and RLP which are normal provided there is no blood. I'm only 16 weeks but my OB mentioned its not unheard of to have nausea on and off through 20+weeks. If you're concerned you could always give your doctor a call but it sounds normal to me.
I agree with pp about nausea mine flairs up every few days and can last throughout the entire pregnancy. If you have constant pain or spotting contact your dr but if it's the short term sharp or doesn't last very long it's most likely growing pains hope your dr appt went well.
Re: 20 wks and nauseous
I agree with PP the cramps and pain sound like RLP, also normal.