Please always follow up with your treatment provider and vein specialist if there is any concern. Also, follow the post procedure instructions for proper healing. For Sclerotherapy treatment performed on spider veins, it could look worse or darker before it looks better. While sclerotherapy can help improve the appearance of spider veins (typically takes 4-6 weeks to see full results), new veins can appear if the underlying problem is not addressed. Our recommendation would be to make an appointment with a vein specialist for further evaluation. Regarding matting, treated areas may cause micro veins to appear, this is a known side effect that can be treated with another sclerotherapy session. It is important to follow up with the vein specialist to make sure you are properly healing and there are no complications from the treatment.All the best!