Make sure you warmup slowly and be sure to stretch for at least 15-20 minutes right after your workout, lengthening all the muscles you worked out.
Make sure give yourself 1-2 days to recover from your workout to build the muscle back.
Eat right and drink a ton of water, vitamins, calcium, enough rest, a protein shake within 60 minutes of your workout to help build the muscle back. Maybe try a lavender epsom salt bath with not too hot water for 20 minutes.
Be careful not to de-motivate yourself by training too hard. Might want to take it back a notch. LISTEN to your body. It is telling you something.
It is great that you are working out. Keep going, just fine tune your workout, Maybe try something different, vary it up.
Also, don't forget that you just started working out. It has been over a year and your body needs time to adjust to the new demands of working out. Be patient with yourself to prevent an injury. If you keep pushing yourself without respecting your body, you will end up further behind with an injury. You won't be able to workout at all if this happens.
So, stay motivated by making small changes to keep yourself motivated and getting stronger each day.
After 3 weeks of working out, your body shouldn't hurt, and you have started a pattern of working out. So you will know how to listen and feed your body to get the results you want and have more energy without being sore.
Good Luck~