Backtesting strategies with historical data using Excel VBA

I'm brand new to using Excel VBA. I've been having trouble with finding a platform/service that allows me to have accurate backtesting results. I notice that the results for profit are skewed because the entry and exit prices are both incorrect. I've been importing historical data (Open, High, Low and Close) onto Excel and manually calculating profit for quite some time now. This is incredibly tedious and time consuming. I want a more efficient way to do this.

The backtesting strategies I've developed aren't based on moving averages or crossovers. Just simple patterns that I've come up with. The strategy is pretty simple.
There must be a series of at least three rising 'low' values in consecutive order. (This would be in column D)
The last 'low' of the rising series must be greater than the proceeding low.

In regards to price entry and exit. The price entry would be the 'low' of the last of the rising 'low' series and the price exit would be the 'close' value of the day that follows the end of the rising 'low' series.

If low[0] is the current day and the low[1] is the previous day. Price entry would be at low[1] (This would be the last 'low' of the rising 'low' series) and price exit would be close[0].

I've coded for the strategy before, but I'm having trouble achieving accurate profit results when it comes to backtesting.



Any advice/help would be greatly appreciated!