My sister is an Asthmatic, she had the nasty virus before Xmas, it went to her chest and started a very bad cycle of Asthma, she could couldn't breath, she managed to get to the doctors, they started her on stronger steroids and, she is already on preventative and daily inhaler.
Last time I spoke to her, it is beginning to ease, the virus can take a long time to go from system, I am still coughing.
She does attend an Asthma Clinic and is monitored, a few years ago my brother nearly died with sever asthma attack, they had to break to front door down to get to him, he had manage to dial 999 before he passed out, he was in intensive care for 48 hours.
Asthma is frightening and should never be underestimated.
Ju ju if it gets too bad ring for help don't take chances.