I guess this post should be over on the Training Q&A forum...but, misplaced topics are "apparently the norm" on Getbig, so what the hell!
I don't know what to advise you on the nausea, as the only time I ever experienced something like this was if I tried to do squats or deads too soon after eating a large meal...I would wait at least three hours after eating a heavy meal and the suggestion for popping anti-acids sounds like a good one.
Hey, its great if you can keep your deadlift reps. high throughout your training career, say 10-25, and not give in to the overwhelming temptation to often test yourself with a 1 RM. In the 5 decades I've been training in gyms all over the U.S., I've seen more lifters injure their themselves doing the DL with the straight bar. Yes, if you used perfect form on every rep, no problem, but that often is not the case with limit attempts or when you try to squeeze out that very last brutal back-rounding rep (and, the next morning/day with your nagging SORE back you REGRET you did!!).
However, the real beauty of the trap bar is that you can start the DL in absolutely the perfect starting position with the knees well bent, hips low, and back absolutely flat. However, with a straight bar, depending upon your height and bone lengths/leverages your shins always contact the bar and this limits many trainees from lowering the hips far enough down, or bending the knees sufficently, to reach an ideal starting position (non-sumo style).
The trap bar is the perfect device to use with straps to do full-range deadlifts in as near perfect form as possible, and practically eliminates (or greatly reduces) the dangerous rounding of the back in an effort to clear the knees. You can even stand on plates/boxes/etc. and get the tops of the thighs parallel, or even BELOW parallel, with the floor doing trap bar DL's. Thus, you are combining the benefits of the squat and DL in one tremendous full-range movement/exercise...arguably the best single BB exercise ever, as you are definitely working more muscles than in the back squat.!
Of course, partial DL's in the power rack, starting the bar just above the knees on the pins, is much safer than the full-range straight bar DL and allows you to overload the affected muscles and can be a very effective strength/muscle builder. However, just like partial squatting in the power rack, it does not work the muscles over their full-range.