Troublebreathing n Oxygen <94 post covid

Hello All I had covid and started 18 days back with diarrhea,Body pain, fever and cold initially. My RT Pcr came out negative whereas blood tests like D Dimer and CRP showed elevation in second week. On 9th day because of fever and extreme dehydration took CT N came out negative but chest cold continued with Nasal Block.. Today my oxygen dropped to 92, 84 few seconds n developed breathlessness due to that.. rushed to hospital n took CT again for admission turned out negative n when checked for O2 that time it was 97.. Need your expert opinions on next further steps.. Currently am taking medicines as prescribed 1. Sompraz D Capsule 1-0-0 2. Pulmoclear 1-0-1 3. Montair 0-0-1 4. Foracort Inhaler 2 Puff 2-0-2 5. Duanose Nasal Spray 2-0-2 Along with this vitamin D, Vitamin C.. Also took ECG last week n it was Normal..