Hi Neenie, welcome to HCM.
Early morning activity is definitely a good habit. However, by drinking red bull after it, you are putting all the 5km run to vain. Its like stuffing back in all the calories that was lost. Exercise should always be taken along with a healthy diet. You have not mentioned detailts with regards to your diet. Your vigorous running should be followed by a healthy diet. Also, the diet depends on your goal if its weight loss
or building up stamina etc. There is a high possibility that your diet in the first half of the day is not appropriate. Ensure you consume a balanced full breakfast which includes some cereal, good protein source, fruits, vegetables and some dairy products. Good luck to you :-) !!!