Should I be concerned about deep vertical lines and darkened area? (Photos)

The deep vertical lines are a pleating effect as your upper abdo incision (longer) has been gathered into the shorter scar below. This the same effect as a curtain - when you open it you shorten it against the curtain rail and it forms pleats. This should settle but may not fully disappear by 3 months. It would be useful to see your PS to discuss these issues and for him to give you advice and reassurance.

Thank you so much for submitting your question. 
You are still extremely early in the recovery phase and while it is a challenge you are going to have to try and be patient. Post tummy tuck swelling can linger upwards of 6-12 months (though most well resolve in the early period). The pleats you see should smooth out over time and will likely not be an issue long term. Yes, people can have a sensitivity to the steri strips and have the redness you describe. 
Thank you for submitting your questions and good luck!

After looking at your photos you are still early in the postop healing area and these pleats that you have should for the most part resolve over the next several months,