If you have a fungal infection, the red line could be caused by that. Are you using any medication to get rid of the fungal infection? If not, you can usually treat topical fungal infections using over-the-counter creams for jock itch or athlete's foot.
Hard to say what the bump is, but if it's at the top, you should keep an eye on it. It could be a cyst forming, which might require medical attention: https://www.mayoclinic.org/diseases-conditions/pilonidal-cyst/symptoms-causes/syc-20376329