english tenses

I'm having some issues with tenses. I am trying to write in past tense but I think I'm mixing it with present tense. Please see below and let me know what you think, please.

"He didn’t speak a word the entire climb, unnerving her. Still, since he never told her to stop, she continued moving upward and soon they were on the roof. Again, he gripped her wrist, this time leading her over to the front of the building, looking over the edge to the street below."

Unnerving, moving, leading and looking are all present tense, but the rest of the sentence is past tense...

Thanks in advance!