The S&P 500 and Nasdaq have both felt pressure as shares of major tech companies came under pressure Monday. Investors continue to keep a close eye on rising Treasury yields, which heighten worries about valuations, particularly for some of the market's most highly valued names.

The average 30-year fixed-rate mortgage rose to 6.91% in the week through Wednesday, from 6.85% as of Dec. 26, according to Freddie Mac data. 15-year mortgage rates jumped to 6.13% from 6% a week earlier.