Buying power refers to the total funds that an investor has available to trade securities, and it equals cash held in the account plus the available margin.

Since the PDT rule says you can't make four or more trades in a five business-day period, in order to not be labeled a Pattern Day Trader, you can't trade again until the next Monday. But you can sell existing holdings provided they were not purchased the same day.

Trading, in simple terms, is the act of buying and selling financial instruments (like shares, forex and indices) without directly owning them, in the hopes of making a profit from changes in their price movements.

you are considered a pattern day trader if you execute four or more "day trades" within five business days—provided that the number of day trades represents more than six percent of your total trades in the margin account for that same five business day period.