If the run to the dryer is excessively long, you might want to upsize the wire, too. Probably not an issue. If you have a multimeter, you could check the voltage at the panel, then again at the dryer with it running. Don't do this if you aren't comfortable and knowledgable about working on power. If there is a significant voltage drop, then you have a bad connection somewhere or the wire is undersized (shouldn't be, though). Could be in the plug, or cord, or maybe even at the panel. Does the breaker get warm, too? Could have a bus bar problem or a bad breaker.